Optical reader applicable to plurality of uses

ABSTRACT

An optical reader capable of reading a bar code in a mounted state when an article carrying the bar code passes and of reading bar codes set in array on a menu sheet in a hand-held state has been disclosed. The optical reader comprises a light source, a scanner that is driven by a drive and scans light emanating from the light source, a plurality of reflection mirrors that reflect scanning light scanned by the scanner and create a scanning pattern composed of a plurality of scan trajectories, a read window through which scanning light reflected from the reflection mirrors is emitted, and a light receiver for receiving light reflected from a mark. The optical reader further comprises a mode changer for changing a plurality of operation modes among which one or ones of the plurality of scan trajectories to be validated for reading are different. The operation modes include a specific scanning ray mode in which reading the mark by tracing only a given scan trajectory constituting the scanning pattern is validated but reading the mark by tracing the other scan trajectories is invalidated. For reading any of bar codes set in array on a menu sheet, the given scan trajectory constituting the scanning pattern will be drawn on a bar code to be read. Since reading by tracing the other scan trajectories is invalid, only the bar code to be read is read.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an optical reader, or moreparticularly, to a compact bar-code reader applicable to portable use.

[0003] In recent years, information input using bar codes has prevailed.For example, when a shopper purchases a product at a store, a bar-codereader is used to read a bar code carried by the product. Thus, theproduct code provided in the form of the bar code can be input and thepurchase can be registered.

[0004] For controlling inventories in a warehouse, it has become amatter of daily practice to read bar codes carried by the inventory orby containers for the inventory and to carry out inventory control onthe basis of the read data.

[0005] Thus, the bar-code reader is employed in information input for avariety of applications. Bar-code readers of optimal forms (shapes orthe like) are used for the respective applications. The presentinvention realizes a bar-code reader usable for various kinds ofapplications.

[0006] 2. Description of the Related Art

[0007] Conventional bar-code readers are broadly divided by applicationinto stationary readers and portable (hand-held) readers.

[0008] The stationary reader is literally a reader placed on, forexample, a cashier's counter or a conveyer for carrying articles. Thestationary reader has a read window. Scanning light such as laser lightis emitted through the read window. The scanning light emitted throughthe read window is irradiated to an article bearing a bar code. Thesurface of the article is scanned by the scanning light. The scanninglight scanned over the article is reflected. The reflected light isreceived through the read window, whereby the bar code is read. Anarticle that is an object of bar-code reading passes a position at adistance from the reader.

[0009] The orientations of bar codes passing in front of the reader arenot always a constant direction but are usually various directions(inclinations). A general stationary reader therefore produces scanninglight so as to generate a scanning pattern created by scanning raystraveling in a plurality of directions, in particular, a scanningpattern created by mutually-intersecting scanning rays.

[0010] A light reception sensor for receiving light reflected from a barcode is incorporated in the stationary reader. Light reflected from abar-code surface is scattered light. A condenser for gathering as muchof the light reflected from a bar code as possible is therefore placedin front of the light reception sensor.

[0011] As mentioned above, the stationary reader is designed to read barcodes of articles passing a position away from the reader. The focalposition of scanning light emitted through the read window is thereforeset to a position away from the read window.

[0012] In the case of the stationary reader, a user is required tomerely pass articles in front of the read window. Bar codes are thenread out. Scanning for bar-code reading is very simple. Maneuverabilityis excellent. In particular, even when it is required to read bar codescarried by a large number of articles for a limited period of time,since the articles need merely be passed in front of the reader,bar-code reading can be achieved efficiently.

[0013] The hand-held reader is a reader which is held in a hand and ofwhich the read window is directed toward articles in order to read barcodes carried by the articles.

[0014] In the case of the stationary reader, since articles must bepassed in front of the read window, when an article, for example, aheavy article or large article is hard to pass the read window, themaneuver for reading is hard to do. In case an article contains liquidor an article cannot be tilted, it is conceivable that the article maybe passed in front of the read window but the bar-code surface thereofmay not be able to be directed toward the read window.

[0015] In contrast, a hand-held reader is designed to approach anarticle for reading. Even if an article bearing a bar code is large orheavy, the bar code can be read readily. Even when an article cannot betilted, a bar code can be read by bringing the reader to the position ofthe bar code.

[0016] Herein, a gun-shaped reader has, similarly to the stationaryreader, a form suitable for reading the bar code of an article locatedrelatively distant. The gun reader has a grip by which a user grasps andoperates the reader.

[0017] In the case of the gun reader, a user holds the grip and directsa read window thereof toward a bar code to be read. A laser light sourceis lit by manipulating a trigger switch formed on the grip. A scanningbeam is then emitted through the read window, whereby the bar code isread out.

[0018] Unlike the aforesaid readers, a touch-system reader is a readerthat is brought into contact with a bar code for reading or that is usedto read a bar code located very near. A light source such as an LED anda light reception sensor such as a CCD are incorporated in the touchreader. For reading a bar code, a light source illuminates the bar-codesurface. Light reflected from the bar code is then received by the lightreflection sensor.

[0019] There is a method to be adopted when bar codes cannot be affixeddirectly to products or the like, wherein: a plurality of bar codes arerecorded on a menu sheet in order to create a so-called bar-code menu;and when it is required to input product information, a necessary barcode is read out. Numerous different bar codes are recorded mutuallyadjacent on the bar-code menu. When an attempt is made to read thebar-code menu, only the bar code to be read must be read by the readerbut unwanted bar codes must not be read thereby.

[0020] However, in the case of the stationary reader or the like,scanning rays to be scanned in a plurality of directions (or sometimesmutually-intersecting scanning rays) are emitted. The scan range coveredby the stationary reader is very wide. When this kind of reader is usedto scan a bar-code menu, the possibility of scanning and readingunnecessary bar codes is very high. It is quite hard to scan only aspecific bar code. Moreover, for reading a bar-code menu using the gunreader, a method in which the reader is distant from or near to thereader menu is conceivable. In this case, when the gun reader is locatedat a distant position, it is hard to align a bar code with a positionscanned by the reader. When the gun reader is too close, the read windowinterferes with locating the position being scanned. When an attempt ismade to read a bar-code menu using either the stationary or gun reader,bar codes that need not to be read are read out. These readers aretherefore unsuitable for reading the bar-code menu.

[0021] By contrast, the touch reader is brought into contact with a barcode or located at a position very close to the bar code. A very limitedrange alone is an object range of reading. The touch reader can easilyread specific bar codes alone selectively and is therefore very suitablefor reading a bar-code menu.

[0022] As mentioned above, readers associated with bar-code read formshave been used in the past. The readers may be suitable for certainapplications but may not be suitable for other applications. The readersare applicable to only specific applications. For coping with variousread forms, readers associated with the read forms must be prepared.

[0023] For example, as mentioned above, it is difficult for thestationary reader to read bar codes borne by articles that are difficultto pass in front of the read window; such as, heavy articles. When thebar codes borne by such articles must be read, the hand-held reader mustbe made ready to operate.

[0024] By contrast, in the case of the hand-held reader, it is requiredto direct the reader toward a bar code. Especially, in the case of thetouch reader, the reader must approach a bar code to such an extent thatit comes into contact with the bar code. The maneuverability for readingis poor. When numerous bar codes must be read in a short period of time,the use of the stationary reader is essential to improvement of readingefficiency.

[0025] Furthermore, since the stationary reader and gun reader scan awide range, there is a possibility of reading excessive bar codes. Thestationary reader and gun reader are therefore unsuitable for reading abar-code menu. Especially, in the case of the gun reader, when thereader is too close to a menu sheet, a bar code is hidden behind theface of the reader. It becomes hard to locate a position of the menusheet being scanned or to check if a bar code that is an object ofreading is being scanned successfully.

[0026] When there is a possibility of reading a bar-code menu, the useof the touch reader is needed. However, the touch reader cannot read abar code located at a distance.

[0027] Consequently, optimal readers must be prepared for various readforms. However, preparing two or three kinds of readers for differentread forms leads to an increase in cost involved in installingequipment. Besides, the case in which the use frequencies of readersdedicated to different applications are the same is rarer than the casein which the use frequencies of some of the readers dedicated tospecific applications are higher. There is difficulty even cost-wise inpreparing readers, which operate in rarely-used forms, just in case.

[0028] For preparing readers that operate in a plurality of forms, anextra space is needed to install the plurality of readers. However, onlya limited space can be allocated to, for example, a cashier's counter.When a store itself is narrow, it cannot afford to install the pluralityof readers. In this case, the idea of installing the plurality ofreaders itself becomes a disadvantageous condition for the store.

SUMMARY OF THE INVENTION

[0029] An object of the present invention is to realize a readerapplicable to different read forms.

[0030] For coping with different read forms using one reader, it isrequired to change the reader among read modes associated with the readforms whenever ti becomes necessary. The present invention ischaracterized in that it realizes a mechanism for manually orautomatically changing read modes optimally for the read forms in whicha reader operates.

[0031] Furthermore, an object of the present invention is to assist inand facilitate the user's work of reading by setting the emissiondirection of a scanning ray according to each read form or by indirectlynotifying the user of the scan direction of a scanning ray.

[0032] Yet another object of the present invention is to design a standneeded to use a reader as a stationary reader so that the stand will beuser-friendly.

[0033] Still another object of the present invention is to improve anoptical system for a reader.

[0034] An optical reader according to the present invention scans a markcarried by an article using scanning light, detects light reflected fromsaid mark, and thus reads information represented by said mark. Theoptical reader comprises: a light source; a scanning means that isdriven by a driving means and scans light emanating from the lightsource; a plurality of reflection mirrors for reflecting scanning lightscanned by the scanning means and creating a scanning pattern composedof a plurality of scan trajectories; a read window through whichscanning light reflected from the reflection mirrors is emitted; and alight receiving means for receiving light reflected from the mark; and amode changing means for changing a plurality of operation modes amongwhich one or ones of the plurality of scan trajectories to be validatedfor reading are different, the plurality of operation modes including aspecific scanning ray mode in which reading the mark using only aspecific scan trajectory constituting the scanning pattern is validatedand reading the mark using the other scan trajectories is invalidated.

[0035] According to the present invention, in the specific scanning raymode, only a specific scan trajectory is validated and the other scantrajectories are invalidated, therefore, other marks except a targetmark are not read. This is particularly effective when bar-codes on amenu sheet are read.

[0036] The read window is divided into a first area and a second area,scanning rays tracing the other scan trajectories are output through thefirst area, and a scanning ray tracing the given scan trajectory isoutput through the second area. The first area is a first read window,and the second area is a second read window independent of the firstread window. The emission direction of a scanning ray tracing the givenscan trajectory is obliquely upwards relative to scanning rays tracingthe other scan trajectories, and the second read window is located abovethe first read window, and the face of the second read window is locatedobliquely to the face of the first read window.

[0037] According to these constitutions, a user can easily recognize theposition from which the given scan trajectory is output.

[0038] The scanning means is a rotary polygon mirror that has aplurality of reflection surfaces and that is driven to rotate by meansof the driving means, and at least one of the plurality of reflectionsurfaces is placed at an angle, which is different from an angle atwhich the other reflection surfaces are placed, with respect to an axisof rotation of the rotary polygon mirror. The reflection mirrors includea first group of reflection mirrors for determining the other scantrajectories and a second group of reflection mirrors for determiningthe given scan trajectory. The second group of reflection mirrorscomprises a single reflection mirror. The other scan trajectories aretraced by a plurality of intersecting scanning rays, and the giventrajectory is traced by a scanning ray scanned in one direction. Thefocal position of scanning rays tracing the other scan trajectories isset to a position separated by a first distance from the first area, andthe focal position of a scanning ray tracing the given scan trajectoryis set to a second position that is closer to the read window than thefirst position. The second position lies on the face of the second areaof the read window. A scan width on the read window permitted by ascanning ray tracing the given scan trajectory is larger than a scanwidth on the read window permitted by scanning rays tracing the otherscan trajectories.

[0039] The optical reader comprises emission position indicating meansfor indicating positions between which a scanning ray tracing the givenscan trajectory is emitted through the read window. The emissionposition indicating means are marks inscribed on the sides of the readwindow. The emission position indicating means are indicating means forindicating the start point and end point of scanning light emittedthrough the read window and notifying a user of the fact that readingthe mark is completed. The emission position indicating means areprojections projecting from positions coincident with the start pointand end point of scanning light emitted through the read window. Theprojections are extending to the focal position of a scanning ray thatis emitted through the read window and that traces the given scantrajectory.

[0040] The second read window is located at a position away from thefirst read window. The optical reader further comprises a transparentcover attached to the face of the second read window, wherein the focalposition of a scanning ray that is emitted through the second readwindow and traces the given scan trajectory lies at the tip of thetransparent cover.

[0041] The optical reader further comprises a mode selection instructingmeans for instructing which of the plurality of operation modes shouldbe selected, wherein the mode changing means selects an operation modeinstructed by the mode selection instructing means. The mode selectioninstructing means is a switch to be manipulated by a user. The switchhas a switch plate that is placed on the top of the switch and thatpressurizes the switch. The mode selection instructing means comprises aplurality of manipulable parts, and the contents of instruction made bythe instructing means are changed into the contents of instruction otherthan selection of any of the plurality of operation modes according towhether one of the plurality of manipulable parts is manipulated or theplurality of manipulable parts are manipulated simultaneously. The modeselection instructing means includes a detecting means located on atleast one of the lateral sides of the optical reader, and any of theplurality of operation modes is selected according to a mounted state ofthe optical reader which is detected on the basis of an output of thedetecting means.

[0042] The optical reader can be mounted in a specific holding member,the mode selection instructing means is a set detecting means fordetecting whether or not the optical reader is mounted in the specificholding member, and when the set detecting means detects that theoptical reader is mounted in the specific holding member, an operationmode other than the specific scanning ray mode is selected. The setdetecting means is a switch to be pushed by a jut formed on the specificholding member when the optical reader is mounted in the specificholding member. The set detecting means is a specific mark detectingmeans that when the optical reader is mounted on the specific holdingmember, detects if scanning light emitted through one of the areas ofthe optical reader has detected the mark. The optical reader furthercomprises a second instructing means for use in designating an operationmode, wherein an operation mode is selected according to a combinationof the state of the first instructing means and the state of the secondinstructing means.

[0043] The mode changing means gives control so that in the givenoperation mode, the light source will be lit only for a period duringwhich a scanning ray tracing the given scan trajectory is being output.The specific scan trajectory validating means gives control so that inany mode other than the given operation mode, the light source is putout for a period during which scanning rays tracing the other scantrajectories are being output. The specific scan trajectory validatingmeans gives control so that in the given operation mode, the operationof the light receiving means will be validated only for a period duringwhich a scanning ray tracing the given scan trajectory is being output.The specific scan trajectory validating means gives control so that inany mode other than the specific operation mode, the operation of thelight receiving means will be invalidated for a period during whichscanning rays tracing the other scan trajectories are being output.Invalidating the operation of said light receiving means is invalidationof the decoding of said read mark.

[0044] In the optical reader, the light source, scanning means,plurality of reflection mirrors, read window, and light receiving meansare stowed in a head. The optical reader further comprises a grip thatis provided with the head and enables a user to grasp the opticalreader. The back side of the head is molded obliquely. The back side ofthe head is molded to be angled in the emission direction of scanninglight emitted through the second area. The back side of the head has aconcave dent formed so that scanning light emitted through the secondarea can be discerned.

[0045] The optical reader further comprises a notifying means fornotifying a user of a selected mode. The notifying means is anindicating means, and the indication form of the indicating means isvaried depending on a selected mode. The indicating means selectscontinual indication or intermittent indication according to a selectedmode. The notifying means is a speaker for generating a notificationsound, and the notification sound is varied depending on a selectedmode. The notifying means is a means for reporting the result of readingof the mark, and the notification form for the result of reading to benotified by the notifying means is varied depending on a selected mode.

[0046] An optical reader according to a second aspect of the presentinvention scans a mark borne by an article using scanning light, detectslight reflected from the mark, and thus reads information represented bysaid mark. The optical reader comprises:

[0047] a light source; a scanning means that is driven by a drivingmeans and scans light emanating from the light source; a plurality ofreflection mirrors for reflecting scanning light scanned by the scanningmeans and creating a scanning pattern composed of a plurality of scantrajectories; a read window through which scanning light reflected fromthe reflection mirrors is emitted; a head including a light receivingmeans for receiving light reflected from the mark; and a grip beingprovided with the head and enabling a user to grasp the optical reader.

[0048] A switch according to the present invention, comprises: a switchbody incorporated in an apparatus; and a switch plate that is attachedto the top of said switch body and that depresses said switch body whenmanipulated, the switch plate is supported at two or more supportingpoints; and when the switch plate is manipulated, the switch plate ispivoted in a manipulated direction with the supporting points asfulcrums and the switch body is pressurized. The supporting points arethree supporting points arranged in the form of a triangle, and theswitch plate is held on the apparatus at the three supporting points.

[0049] A stand according to the present invention is used to hold anoptical reader. The optical reader has a read window through whichscanning light is emitted and a grip enabling a user to grasp saidoptical reader, and which scans a mark borne by an article usingscanning light emitted through said read window, detects light reflectedfrom said mark, and thus reads information. The stand comprises: aholder section in which said grip is mounted so that said grip can bedismounted freely; and

[0050] a base for supporting said holder section so that the holdersection can pivot, said holder section having a slit, through which acable coupled with the optical reader can pass, on the same side thereofas the side of said optical reader having said read window. A concavedent is formed from a position on the base coincident with a lower endof the grip of the optical reader mounted toward the forward side of thestand. The holder section has a member to be actuated with aninstruction sent from the optical reader so that a state in which theoptical reader is mounted on the stand can be reported to the opticalreader. The member is shaped like a jut, and when the optical reader ismounted on the stand, the member pushes the instructing means. Themember is a mark readable by the optical reader, and the mark is locatedat a position enabling scanning light emanating from the optical readermounted on the stand to scan the mark.

[0051] A stand according to another aspect of the present invention isused to mount an optical reader on it. The optical reader includes aread window through which scanning light is emitted and a grip enablinga user to grasp the optical reader, and which scans a mark borne by anarticle using scanning light emitted through the read window, detectslight reflected from the mark, and thus reads information. The standcomprises a stand member on which the optical reader is mounted in sucha manner that the grip of the optical reader will face laterally. Thestand further comprises:

[0052] a holder section in which the grip is mounted so that the gripcan be dismounted freely; and a base for supporting said holder sectionso that said holder section can pivot, the stand member having a tongue,which is inserted into the holder section so that the tongue can beremoved freely, on a bottom thereof. When the optical reader is mountedin the stand member, the optical reader is held at an angle at which atleast one scanning pattern, which is composed of a group of scanningrays, of scanning patterns created by scanning rays emitted through theread window of the optical reader, becomes horizontal.

[0053] An optical unit for an optical reader according to the presentinvention comprises a plurality of reflection mirrors; a laser lightsource; a light reception sensor; a condenser mirror that has a planemirror, which reflects laser light emanating from the laser lightsource, around the center thereof and that gathers incident light to thelight reception sensor; a rotary scanning means that has a plurality ofreflection surfaces for reflecting laser light reflected from said planemirror, that is driven to rotate by means of a driving means, and thatthus scans the laser light; and a frame which is molded as a united bodyand in which the reflection mirrors, the laser light source, the lightreception sensor, the condenser mirror, and the rotary scanning meansare locked. The rotary scanning means is mounted on the frame viacushioning member. The condenser mirror has both edges thereof supportedby the frame; one edge of the condenser mirror is supported so that itcan move back and forth; the other edge of the condenser mirror issupported so that it can pivot with an axis of pivoting extending in alongitudinal direction of the condenser mirror as a center.

[0054] An optical unit according to another aspect of the presentinvention comprises:

[0055] an optical part having a first and second stems formed coaxiallyon both edges thereof and a third stem formed vertically to the secondstem on one of the edges thereof; and a frame on which the optical partis mounted, and which includes a first slit-like bearing into which thefirst stem is fitted, a second bearing into which the second stem isfitted, and a third elongated bearing into which the third stem isfitted and which forms an arc with the second bearing as a center.

BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The present invention will be more clearly understood from thedescription as set below with reference to the accompanying drawings,wherein:

[0057]FIG. 1 is a diagram showing a conventional stationary reader;

[0058]FIGS. 2A and 2B are a sectional view and perspective oblique viewof the conventional stationary reader;

[0059]FIG. 3 is a view showing a conventional gun reader;

[0060]FIG. 4 is a view showing a conventional touch reader;

[0061]FIGS. 5A and 5B are views showing a problem occurring when the gunreader is used to read a bar-code menu;

[0062]FIG. 6 is a front view of a reader of an embodiment of the presentinvention;

[0063]FIGS. 7A and 7B are a perspective oblique view and side sectionalview of the reader of the embodiment;

[0064]FIG. 8 is a diagram showing the emission direction of scanninglight reflected by a fourth reflection surfaces;

[0065]FIG. 9 is a diagram showing the emission direction of scanninglight reflected by a fourth reflection surface;

[0066]FIG. 10 is a diagram showing scanning patterns supplied by thereader of the embodiment;

[0067]FIG. 11 is a diagram showing scanning patterns within readwindows;

[0068]FIG. 12 is a diagram showing scanning patterns at a distance fromthe read windows;

[0069]FIGS. 13A to 13C are views showing read forms permitted by thereader of the embodiment;

[0070]FIG. 14 is a view showing another embodiment of a reader;

[0071]FIG. 15 is a four-side view of the reader shown in FIG. 14;

[0072]FIG. 16 is a view showing a state in which the reader shown inFIG. 14 is mounted on a stand;

[0073]FIG. 17 is a view showing a state in which the reader shown inFIG. 14 is used as a hand-held reader;

[0074]FIG. 18 is a view showing a state in which the reader shown inFIG. 14 is used to read a bar-code menu;

[0075]FIG. 19 is a diagram showing a structure for lighting a pluralityof indicators using a single light source;

[0076]FIGS. 20A and 20B are views showing a stand on which a reader ismounted;

[0077]FIG. 21 is a three-side view of a stand in accordance with anembodiment;

[0078]FIG. 22 is a four-side view of a stand on which a reader ismounted;

[0079]FIG. 23 is a view showing a pivotable range of a holder section ofthe stand;

[0080]FIG. 24 is a diagram showing a plate attached to the bottom of abase of the stand;

[0081]FIG. 25 is a diagram showing a state in which the plate isattached to a wall;

[0082]FIG. 26 is a view showing a state in which the stand is hung onthe wall;

[0083]FIG. 27 is a side sectional view of the stand hung on the wall;

[0084]FIG. 28 is an explanatory diagram concerning a stand tiltmechanism;

[0085]FIG. 29 is a side view of the tilt mechanism;

[0086]FIG. 30 is a front view of the tilt mechanism;

[0087]FIG. 31 is a view showing a laying stand and a stand body;

[0088]FIG. 32 is a view showing the laying stand on which the reader ismounted;

[0089]FIGS. 33A and 33B are views showing the laying stand on which thereader is mounted with the grip of the reader jutted out right and left;

[0090]FIG. 34 is a view showing an erecting stand;

[0091]FIG. 35 is a view showing a laying stand;

[0092]FIG. 36 is a view showing a polygon mirror having a mechanism forchecking a scan position;

[0093]FIG. 37 is a diagram showing the relationship between a sensoroutput and mirror position detection signal;

[0094]FIG. 38 is a block diagram of a reader;

[0095]FIG. 39 is a flowchart describing a procedure of read mode change;

[0096]FIG. 40 is a flowchart describing light source lighting control tobe performed according to a floor mirror over which scanning light isscanned (read mode change);

[0097]FIG. 41 is a timing chart showing waveforms of output signalsprovided by the components of a reader during light source lightingcontrol;

[0098]FIG. 42 is a view showing a mode selection switch formed on theback side of a reader;

[0099]FIG. 43 is a view showing a state in which the mode selectionswitch is manipulated by an index finger;

[0100]FIG. 44 is a view showing a state in which the mode selectionswitch is manipulated by a thumb;

[0101]FIGS. 45A and 45B are views showing a switch plate and a switch;

[0102]FIGS. 46A and 46B are diagrams showing a pressed position of theswitch plate and fulcrums;

[0103]FIG. 47 is a view showing a reader having a switch on the frontside of a grip thereof;

[0104]FIG. 48 is a view showing a reader having side switches;

[0105]FIG. 49 is a timing chart concerning control of a light detectioncircuit according to the position of a floor mirror scanned by scanninglight;

[0106]FIG. 50 is a flowchart describing a procedure of light detectioncircuit control;

[0107]FIG. 51 is a flowchart describing a procedure of decoding control;

[0108]FIG. 52 is a side sectional view of a reader in which a floormirror E1′ is movable;

[0109]FIG. 53 is a diagram concerning light source control performed bythe reader shown in FIG. 52;

[0110]FIG. 54 is a flowchart describing a procedure of read mode changeperformed by the reader having the movable floor mirror;

[0111]FIG. 55 is a view showing a reader laid on a tabletop;

[0112]FIG. 56 is a view showing a reader having mode detection sensorson the lateral sides thereof;

[0113]FIG. 57 is a view showing a state in which the reader having themode detection sensors is laid on a tabletop;

[0114]FIG. 58 is a flowchart describing a procedure of read mode changebased on the mode detection sensors;

[0115]FIG. 59 is a flowchart showing a procedure of read mode change inwhich the mode selection switch and mode detection sensors are used incombination;

[0116]FIG. 60 is a reader having detection switches on the lateral sidesthereof;

[0117]FIG. 61 is a flowchart describing a procedure of read mode changeusing the mode detection switches;

[0118]FIG. 62 is a view showing a reader of which stand has a detectionjut on the base thereof and which has a detector in the grip thereof;

[0119]FIG. 63 is a flowchart describing a procedure of read mode changeperformed by the reader shown in FIG. 62;

[0120]FIG. 64 is a flowchart describing another procedure of read modechange performed by the reader shown in FIG. 62;

[0121]FIGS. 65A and 65B are views showing a read mode change markinscribed on a laying stand;

[0122]FIG. 66 is a flowchart describing a procedure of read mode changebased on the mark;

[0123]FIG. 67 is a view showing a reader having a grip sensor;

[0124]FIG. 68 is a flowchart describing a procedure of read mode changebased on the grip sensor;

[0125]FIG. 69 is a view showing a reader having a scan directionindicator mark;

[0126]FIG. 70 is a view showing a reader having LED indicators on thelateral sides thereof;

[0127]FIG. 71 is a view showing a reader having scan position indicatorprojections;

[0128]FIG. 72 is a view showing a reader having scan position indicatorjuts on a cover thereof;

[0129]FIG. 73 is a view showing a reader having a transparent cover;

[0130]FIG. 74 is a view showing a reader having a notch in a coverthereof;

[0131]FIG. 75 is a view showing a reader having a concave part on theback side thereof;

[0132]FIGS. 76A and 76B are views showing a scanning ray emissiondirection and the back side of a reader;

[0133]FIGS. 77A and 77B are diagrams showing the relationship betweenincidence and reflection of scanning light to and from a bar-codesurface;

[0134]FIG. 78 is a side sectional view of a reader;

[0135]FIG. 79 is a view showing an optical frame and optical parts;

[0136]FIG. 80 is a view showing the optical frame in which the parts arelocked;

[0137]FIG. 81 is a view showing the optical frame in which the parts arelocked;

[0138]FIG. 82 is a view showing the optical frame in which the parts arelocked;

[0139]FIG. 83 is a view showing the optical frame in which the parts arelocked;

[0140]FIG. 84 is a view showing a condenser mirror;

[0141]FIG. 85 is a view showing the condenser mirror to be attached tothe optical frame;

[0142]FIG. 86 is a view showing a reader that supplies a parallel-rayscanning pattern through a second read window;

[0143]FIG. 87 is a view showing a reader that supplies a raster-formscanning pattern through a second read window;

[0144]FIG. 88 is a side sectional view of a reader in which a floormirror is driven;

[0145]FIG. 89 is a flowchart describing a procedure of actuator drive;

[0146]FIG. 90 is a side sectional view of a reader in which scanninglight emitted through a second read window is condensed;

[0147]FIGS. 91A to 91C are diagrams for explaining the relationshipbetween a diameter of light and bar-code reading;

[0148]FIG. 92 is a view showing another example of a reader in whichscanning light emitted through a second read window is condensed;

[0149]FIG. 93 is a block diagram of a reader;

[0150]FIG. 94 is a flowchart describing a procedure of changingindicators of reading modes;

[0151]FIG. 95 is a flowchart describing a procedure of rumbling soundchange to be performed for notifying read modes using rumbling sounds;

[0152]FIG. 96 is a flowchart describing a procedure of rumbling soundchange to be performed for notifying read modes using long and shortrumbling sounds;

[0153]FIG. 97 is a flowchart describing a procedure of rumbling soundchange to be performed for notifying read modes using large- andsmall-volume rumbling sounds;

[0154]FIG. 98 is a flowchart describing a procedure of rumbling soundchange to be performed for notifying read modes using the differentnumbers of rumbling sounds;

[0155]FIG. 99 is a flowchart describing a procedure of rumbling soundchange to be performed for notifying read modes using high- andlow-pitch rumbling sounds;

[0156]FIG. 100 is a flowchart describing indicator state change controlto be performed when read modes are notified according to the indicationmode of indicators;

[0157]FIG. 101 is a view showing a reader having one read window(divided into a plurality of areas);

[0158]FIG. 102 is a perspective oblique view showing a reader in whichreading is validated in single-scanning mode during a period duringwhich part of scanning rays constituting a multi-scanning pattern isemitted; and

[0159]FIG. 103 is a view showing the appearance of the reader shown inFIG. 94.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0160] Before proceeding to a detailed description of the preferredembodiments of the present invention, prior art bar-code readers will bedescribed with reference to the accompanying drawings thereto for aclearer understanding of the differences between the prior art and thepresent invention.

[0161]FIG. 1 is a view showing the appearance of an example of astationary bar-code reader.

[0162] A stationary reader is placed on, for example, a cashier'scounter or a conveyer for transporting articles. The stationary readerhas a read window 13. Scanning light 10 such as laser light is emittedthrough the read window. The scanning light emitted through the readwindow is irradiated to an article bearing a bar code. The surface ofthe article is scanned by the scanning light. The scanning light scannedover the article is reflected. The reflected light is received throughthe read window, whereby the bar code is read. Articles that are objectsof bar-code reading pass a position at a distance from the reader.

[0163]FIGS. 2A and 2B are views showing the internal components of thestationary reader shown in FIG. 1. FIG. 2A is a side sectional view ofthe reader, and FIG. 2B is a perspective oblique view of the internalcomponents of the reader.

[0164] A laser light source 21 for emitting laser light is incorporatedby the reader. Laser light emanating from the laser light source isreflected and scanned by a polygon mirror 22 that is driven to rotate bymeans of a motor and that has a plurality of reflection surfaces, andthen enters a patterning mirror 23.

[0165] The orientations of bar codes passing in front of the reader arenot always a constant direction but usually various directions(inclinations). A general stationary reader therefore produces scanninglight so as to generate a scanning pattern created by scanning raystraveling in a plurality of directions, or in particular, a scanningpattern created by mutually-intersecting scanning rays. In the readershown in FIG. 1, the scanning pattern is composed of three scanningrays.

[0166] For producing a plurality of scanning rays, the patterning mirror23 is incorporated in the stationary reader. As shown in FIG. 2B, thepatterning mirror includes the same number of mirrors as the number ofscanning rays to be generated. In FIG. 2B, the patterning mirrorincludes three mirrors. A bar-code surface is therefore, as shown inFIG. 2B, scanned using the scanning pattern created by threeintersecting scanning rays. Due to this way of scanning, even if a barcode 41 is not level, the bar code can be scanned.

[0167] A light reception sensor 25 for receiving light reflected from abar code is incorporated in the stationary reader. Light reflected froma bar-code surface is scattered light. A condenser lens 24 for gatheringas much of the light reflected from a bar code as possible is thereforeplaced in front of the light reception sensor.

[0168] As described previously, the stationary reader is designed toread bar codes of articles passing a position away from the reader. Thefocal position of scanning light emitted through the read window is setto a position away from the read window.

[0169] In the case of the stationary reader, a user should merely haveto pass articles in front of the read window. Bar-code reading is thencarried out. The maneuver for reader bar codes is very simple. Themaneuverability of the reader is therefore excellent. In particular,when it is required to read bar codes carried by a large number ofarticles for a short period of time, the articles should merely bepassed in front of the reader. Bar-code reading can be achievedefficiently.

[0170]FIGS. 3 and 4 are views showing an example of a hand-held reader.FIG. 3 shows a so-called gun-shaped reader. FIG. 4 shows a so-calledtouch-system reader.

[0171] The hand-held reader is a reader which is held by a hand and ofwhich a read window is directed toward an article in order to read a barcode carried by the article.

[0172] In the case of the stationary reader, articles must be passed infront of the read window. For an article, for example, a heavy articleor large article that is difficult to make pass the read window, themaneuver for reading is difficult. When an article cannot be tiltedbecause it contains liquid, it is conceivable that even if the articlecan be passed in front of the read window, the bar-code surface thereofcannot be directed toward the read window.

[0173] In contrast, in the case of the hand-held reader, the reader canapproach an article for reading. Even if an article bearing a bar codeis large or heavy, the bar code can be read readily. As for an articlethat cannot be tilted, if the reader is drawn close to the position of abar code, the bar code can be read.

[0174] Similarly to the stationary reader, the gun reader has a formsuitable for reading a bar code of an article located at a relativelydistant position. The gun reader is, as shown in FIG. 3, broadly dividedinto a head 11 and a grip 12. A light source, scanning mirrors includinga polygon mirror and galvano-mirror, and a light reception sensor forsensing light reflected from a bar code are incorporated in the head.The grip is held by a user when the user operates the reader. A powersupply or the like may be stowed in the grip.

[0175] In the case of the gun reader, a user holds the grip and directsa read window 13 toward a bar code to be read. When a trigger-liketrigger switch 15 a formed on the grip is manipulated, a laser lightsource is lit. A scanning beam is emitted through the read window,whereby the bar code is read.

[0176] Unlike the aforesaid readers, as shown in FIG. 4, the touchreader is brought into contact with a bar code 41 for reading or used toread a bar code located very close.

[0177] A light source such as an LED and a light reflection sensor areincorporated in the touch reader. For reading a bar code, a light sourceilluminates the bar code. Light reflected from the bar code is receivedby the light reception sensor.

[0178] There is a method to be adopted when a bar code cannot be affixeddirectly to a product or the like, wherein: a bar-code menu is createdby recording a plurality of bar codes on a menu sheet 4; and wheninputting product information is needed, a necessary bar code is read.Numerous different bar codes are recorded adjacently on the bar-codemenu. When an attempt is made to read the bar-code menu, only a bar codeto be read by a reader must be read but unwanted bar codes must not beread thereby.

[0179] However, in the case of the stationary reader, scanning rays tobe scanned in a plurality of directions (or sometimesmutually-intersecting scanning rays) are emitted. The scan range coveredby the stationary reader is very wide. When this kind of reader is usedto scan a bar-code menu, the possibility of scanning and readingunwanted bar codes is very high. Besides, it is very hard to scan only aspecific bar code. When the gun reader is used to read the bar-codemenu, the reader may presumably be distant from the bar-code menu asshown in FIG. 5A or near to the bar-code menu as shown in FIG. 5B. Inthis case, when the reader is distant, it becomes hard to align a barcode with a scan position of the gun reader. When the gun reader is toonear, the read window interferes with checking of a position beingscanned.

[0180] When an attempt is made to read a bar-code menu using either thestationary or gun reader, a bar code that need not be read is read.These readers are therefore unsuitable for reading of the bar-code menu.

[0181] By contrast, in the case of the touch reader, the reader isbrought into contact with a bar code or approached very closely to thebar code. A quite limited range is therefore an object range of reading.The touch reader can selectively read specific bar codes alone and istherefore very suitable for reading of a bar-code menu.

[0182] As mentioned above, readers associated with bar-code read formshave been employed in the past. The readers are suitable for certainapplications but may not be suitable for other applications. The readersare applicable to only specific applications. For coping with variousrad forms, readers associated with the read forms must be prepared.

[0183]FIG. 6 is a view showing the appearance of a bar-code reader of anembodiment of the present invention.

[0184] The reader of this embodiment has the ability to cope with theforms associated with the stationary reader, gun-shaped reader, andtouch-system reader. The one reader are therefore applicable todifferent uses.

[0185] In FIG. 6, reference numeral 1 denotes a reader body. 2 denotes astand on which the reader body 1 is mounted. The reader body 1 has ahead 11, in which a light source, scanning means, and light receivingmeans (which are not shown) are incorporated, and a grip 12 that can beheld by a user.

[0186] A first read window 13 a and a second read window 13 b are formedon the front side of the head 11. The first read window 13 a has a largearea. In the reader shown in FIG. 6, the first read window is shapedlike a sector. The shape of the window is not limited to the one shownin FIG. 6. The shape may be a square or the like. The second read window13 g has a smaller area than the first read window 13 a and has astraight laterally-elongated shape. The shape of the second read windowis also not limited to the one shown in FIG. 6.

[0187] The first read window 13 a and second read window 13 b supply afirst scanning pattern and second scanning pattern that are mutuallydifferent. The details of the scanning patterns will be described later.The scanning patterns associated with different read forms are supplied.

[0188] A cable 3 is coupled with an end of the grip 12. The other end ofthe cable 3 is coupled with an external unit such as a POS terminal thatis not shown. The cable 3 is used to supply power to the reader body 1and to transmit read data (bar-code data) produced in the reader body 1to the external unit.

[0189] A speaker 19 for generating a notification sound used to notify auser of a result of bar-code reading is located on the front side of thereader.

[0190]FIGS. 7A and 7B are views showing the internal components of thereader shown in FIG. 6, especially, of the head. FIG. 7A is aperspective oblique view showing the components from the side of theread windows of the head, and FIG. 7B is a side sectional view showingthe head. In FIGS. 7A and 7B, the same functional parts as those inFIGS. 2A and 2B are assigned the same reference numerals. Thedescription of the functional parts will be omitted. A semiconductorlaser or the like is used as a light source 21. Reference numeral 26denotes a reflection mirror (condenser mirror) realized with a concavemirror. A planar small mirror 26′ is placed around the center of theconcave mirror. The reflection mirror 26 and small mirror 26′ may beprovided as separate members and joined with each other afterward.Alternatively, the reflection mirror 26 and small mirror 26′ may beformed unitedly using, for example, a resin or the like. Thereafter, areflection membrane may be deposited on the united body. Light emanatingfrom the light source 21 is emitted toward the small mirror 26′.

[0191] The reflection surface of the small mirror 26′ is formed at suchan angle that it allows laser light reflected from the small mirror 26′to be irradiated to a polygon mirror 22. The polygon mirror 22 shown inFIGS. 7A and 7B has a reflection surface on each of the four sidesthereof. The number of reflection surfaces is not limited to four. Thepolygon mirror 22 is attached to the shaft of a motor that is not shown,and driven to rotate by means of the motor. The inclinations (0) of thefour sides of reflection surfaces of the polygon mirror with respect toa vertical line are different from one another. The inclination of thepolygon mirror itself can be set freely. The inclination of one of thesides of the polygon mirror may be different from those of the othersides. Alternatively, all the sides may share the same inclination.

[0192] Laser light reflected from the reflection surfaces of the polygonmirror 22 is scanned in responsive to the rotation of the polygon mirrorand then enters floor mirrors 23-1 to 23-8.

[0193] The floor mirrors are a plurality of mirrors and produce aplurality of scanning rays constituting a scanning pattern. The floormirrors shown in FIG. 2 are eight mirrors. Among them, the floor mirrors23-1 to 23-5 are arranged adjacently in such a manner that they definean arc. All the reflection surfaces are directed inward. The floormirrors 23-3 and 23-7 are placed above the floor mirrors 23-1 and 23-5respectively, and the reflection surfaces thereof are directed in thesame direction as those of the floor mirrors 23-1 and 23-5. The floormirrors 23-1 and 23-7 are placed under the first read window 13 a andconstitute a first group of floor mirrors.

[0194] The floor mirror 23-8 is placed under the second read window 13b. The floor mirror 23-8 has a thinner and longer shape than the otherfloor mirrors. A scanning ray emanating from the floor mirror 23-8therefore lasts longer than those emanating from the other floor mirrors23-1 to 23-7 at the levels of the read windows.

[0195] Herein, assuming that a scanning ray permits a large scan width,compared with a scanning ray permitting a small scan width, a width tobe scanned by the former scanning ray within the same scan time islarger. In other words, as long as a width to be scanned is unchanged,the scan speed of the former scanning ray is lower. Bars of smallerthicknesses can therefore by detected. This leads to a substantialincrease in resolution. Thus, it is advantageous to increase a scanwidth permitted by a scanning ray. For increasing all scan widths, allthe floor mirrors must be made wider. This results in a larger head. Inthis embodiment, therefore, the floor mirror 23-8 alone is realized witha long mirror in consideration of the position of installation thereof.The floor mirror 23-8 is regarded as a second group of floor mirrors.

[0196] The numbers of floor mirrors constituting the first and secondgroups of floor mirrors can be properly selected according to read formsthat are presumably handled by the reader. The first and second groupsof floor mirrors may each include a plurality of floor mirrors. Scanninglight emitted from each of the first and second group of floor mirrorsthrough an associated read window should merely cope with a presumedread form.

[0197] Scanning light reflected from the polygon mirror 22 is reflectedupward in FIG. 7B by the floor mirrors 23-1 and 23-8 and emitted throughthe read window associated with the floor mirrors. Scanning lightreflected from the floor mirrors 23-1 to 23-7 is emitted through thefirst read window 13 a and creates a first scanning pattern. The firstscanning pattern is therefore basically composed of seven scanning rays.Scanning light reflected from the floor mirror 23-8 is emitted throughthe second read window 13 b. A second scanning pattern is basicallycreated by one scanning ray permitting a large scan width.

[0198] As shown in FIG. 7B, the mounting position of the floor mirrors23-1 to 23-5 and those of the floor mirrors 23-6 to 23-8 are deviatedvertically. As described previously, the reflection surfaces of thepolygon mirror have different inclinations. When laser light isirradiated to a reflection surface of the polygon mirror drawn with asolid line in FIG. 7B, scanning light is reflected from the floormirrors 23-1 to 23-5 along a path drawn with a solid line in FIG. 7B.Scanning light incident to the floor mirror 23-1 to 23-5 is reflectedupward, and emitted through the first read window 13 a.

[0199] By the way, a reflection surface of the polygon mirror drawn witha dashed line in FIG. 7B faces up compared with the reflection surfacedrawn with a solid line. Scanning light (drawn with a dashed line inFIG. 7B) reflected by the reflection surface drawn with a dashed line isreflected upward more greatly than the scanning light reflected by thereflection surface drawn with a solid line, and then enters the floormirrors 23-8 and floor mirrors 23-6 and 23-7 which are mounted above thefloor mirrors 23-1 to 23-5. Of the scanning light, a scanning rayincident to the floor mirror 23-8 is reflected and emitted through thesecond read window 13 b. Scanning rays incident to the floor mirrors23-6 and 23-7, which are not shown, are reflected by the mirrors andemitted through the first read window 13 a.

[0200] As mentioned above, since the reflection surfaces of the polygonmirror are inclined differently, a floor mirror to which scanning lightis incident is selected according to a reflection surface by which thescanning light is reflected. A scanning pattern dependent on the floormirrors is supplied through an associated read window.

[0201] Light reflected from a bar code enters the light reception sensor25 along the same path as the emission path of scanning light. Forexample, reflected light of scanning light reflected by the floor mirror23-1 travels along the path of the first read window, floor mirror 23-1,polygon mirror 22, reflection mirror 26, and light reception sensor 25.Herein, light reflected from a bar code is scattered light. Forincreasing the quantity of light received by the light reception sensorG, the reflection mirror 26 that is a concave mirror is placed on thelight path. The reflection mirror gathers the light reflected from thebar code and routs it to the light reception sensor 25. The focalposition of the reflection mirror 26 is set on the light receptionsurface of the light reception sensor 25. This is intended to improvethe light reflection efficiency of the light reception sensor 25.

[0202] Next, emitting scanning light will be described.

[0203]FIGS. 8 and 9 are diagrams for explaining the emitted state ofscanning light. FIG. 8 shows a state in which scanning light isreflected by the first to third reflection surfaces of the polygonmirror, while FIG. 9 shows a state in which scanning light is reflectedby the fourth reflection surface of the polygon mirror.

[0204] As shown in FIG. 8, in case scanning light is reflected by thefirst, second, and third reflection surfaces of the polygon mirror(corresponding to the reflection surface drawn with a solid line in FIG.7B), the scanning light is reflected by the floor mirrors 23-1 to 23-5(the floor mirrors 23-4 and 23-5 are not shown), and emitted through thefirst read window 13 a. Herein, since the surfaces of the polygon mirrorhave different angles of reflection, a scanning ray reflected from thefirst reflection surface falls on a first position e1 of a floor mirror,a scanning ray reflected from the second reflection surface falls on asecond position e2 of the floor mirror, and a scanning ray reflectedfrom the third reflection surface falls on a third position e3 of thefloor mirror. Thus, the incident positions are different from oneanother.

[0205] The angles of incidence of the three scanning rays entering thefloor mirror are therefore different from one another. The emissiondirection of a scanning ray reflected from each floor mirror variesdepending on the incident position. For example, the scanning rayreflected from the first position e1 is emitted in a direction a in FIG.8. The scanning ray reflected from the second position e2 is emitted ina direction b in FIG. 8. The scanning light reflected from the thirdposition e3 is emitted in a direction c in FIG. 8.

[0206] Since the emission directions of scanning rays thus differ fromone another, a scanning pattern supplied through the first read windowvaries slightly in terms of scan position, and is available in threedifferent kinds. In the case shown in FIG. 8, the three scanning rays a,b, and c trace trajectories that are mutually parallel. Thus, when onescanning rays, a range scanned by the scanning rays can be expanded.This leads to an increase in probability of scanning a bar code passingin front of a read window. Eventually, it becomes possible to improvethe success rate of bar-code reading.

[0207]FIG. 9 shows a state in which scanning light is reflected by thefourth reflection surface of the polygon mirror (corresponding to thereflection surface drawn with a dashed line in FIG. 7B). The fourthreflection surface faces slightly up compared with the first to thirdreflection surfaces. The scanning light reflected from the fourthreflection surface of the polygon mirror therefore falls on the floormirrors 23-6 to 23-8 (the floor mirror 23-7 is not shown) mounted at aposition higher than the floor mirrors 23-1 to 23-5.

[0208] Of the scanning light, scanning rays reflected from the floormirrors 23-6 and 23-7 are emitted as a scanning ray b through the firstread window. By contrast, a scanning ray reflected from the floor mirror23-8 is emitted as a scanning ray a through the second read window.Owing to this structure, the read window through which scanning light isemitted can be changed from one to the other according to the length ofa period during which laser light is scanned.

[0209] As mentioned above, the number of scanning rays generated duringone rotation of the polygon mirror can be increased by differentiatingthe inclinations of the reflection surfaces of the polygon mirror.Besides, the read window through which scanning light is emitted can bechanged from one to the other.

[0210]FIG. 10 is a diagram showing scanning patterns supplied throughthe first and second read windows. Straight lines shown in FIG. 10indicate trajectories of scanning rays. Reference numerals assigned tothe scanning rays indicate the associated floor mirrors and reflectionsurfaces of the polygon mirror. For example, 23-1 denotes a trajectoryof a scanning ray reflected from the floor mirror 23-1, and implies thatthis scanning ray is reflected from the first reflection surface of thepolygon mirror.

[0211] Straight lines 23-1 to 23-7 indicate trajectories of scanningrays emitted through the first read window. Straight lines 23-8indicates a trajectory of a scanning ray emitted through the second readwindow.

[0212] Scanning rays reflected from the first to third reflectionsurfaces of the polygon mirror fall on the floor mirrors 23-1 to 23-5.Each of the floor mirrors therefore generates three scanning rays duringone rotation of the polygon mirror. Three scanning rays reflected fromthe floor mirrors trace trajectories that are mutually parallel withgiven gaps among them.

[0213] A scanning ray emanating from the floor mirror 23-1 issubstantially horizontal relative to the read window. Scanning raysemanating from the floor mirrors 23-2 and 23-5 are angled substantiallyat 45°. The scanning ray emanating from the floor mirror 23-2 anglesright, while the scanning ray emanating from the floor mirror 23-5angles left.

[0214] Likewise, a scanning ray emanating from the floor mirror 23-3angles right, while a scanning ray emanating from the floor mirror 23-4angles left. These scanning rays are angled more sharply than thoseemanating from the floor mirrors 23-2 and 23-5.

[0215] Scanning light reflected from the fourth reflection surface ofthe polygon mirror enters the floor mirrors 23-6 to 23-8. While thepolygon mirror is making one rotation, each of the floor mirrors 23-6 to23-8 generates one scanning ray.

[0216] A scanning ray emanating from the floor mirror 23-6 is scanned atsubstantially the same angle as (but is slightly mismatched with) theone emanating from the floor mirror 23-2. The scan position of thescanning ray is a position at which the scanning ray emanating from thefloor mirror 23-2 does not scan. Likewise, the inclination of a scanningray emanating from the floor mirror 23-7 is slightly different from thatof the one emanating from the floor mirror 23-5. The scan position ofthe scanning ray is a position at which the scanning ray emanating fromthe floor mirror 23-5 does not scan.

[0217] Each of the floor mirrors 23-6 and 23-7 generates one scanningray during one rotation of the polygon mirror. Owing to this smallnumber of scanning rays emanating from each of the floor mirrors 23-6and 23-7, the number of scanning rays emitted through the first readwindow can be increased. Eventually, the possibility that a bar code isscanned be improved.

[0218] As mentioned above, scanning rays to be scanned are emitted inabout five directions through the first read window. Even if bar codespassing the first read window are tilted in various directions, any ofthe scanning rays can scan the bar codes in units of a readable length.Consequently, the probability of reading a bar code can be improved. Ascanning pattern dependent on the floor mirrors 23-1 to 23-5 is createdby three scanning rays that are scanned mutually parallel. Even if a barcode passes a position that may not be able to be scanned by a singlescanning ray, since the number of scanning rays is large, a wide scanrange is ensured. Consequently, if a plurality of scanning rays areemployed, any of them can scan the bar code. Eventually, the probabilityof reading a bar code further improves.

[0219] A scanning ray emanating from the floor mirror 23-8 is scannedhorizontally and emitted straight through the second read window.Herein, the length of the floor mirror 23-8 is longer than those of theother floor mirrors 23-1 to 23-7. The scanning ray emanating from thefloor mirror 23-8 therefore lasts longer.

[0220] A scanning ray emitted through the second read window has thescan direction thereof fixed. The scanning ray is therefore suitable fora bar code or an object of reading of which orientation is determined inadvance or for a bar code of which position can be aligned in adirection optimal for reading.

[0221] Thus, the reader of this embodiment produces a total of 18scanning rays during one rotation of the polygon mirror.

[0222] In the example of FIG. 10, each of the floor mirrors 23-6 to 23-8produces one scanning ray during one rotation of the polygon mirror. Thenumber of scanning rays emanating from each floor mirror can be variedby modifying the number of reflection surfaces of the polygon mirror fortransmitting scanning light to floor mirrors. The number of scanningrays emanating from each floor mirror is therefore not limited to thevalue shown in FIG. 10. The reader shown in FIG. 10 has the preconditionthat only one scanning ray is emitted through the second read window.

[0223]FIG. 11 is a diagram showing trajectories constituting scanningpatterns on read surfaces. As shown in FIG. 11, a total of 17 scanningrays are emitted through the first read window, while one scanning raypermitting a long scan width is emitted through the second read window.

[0224]FIG. 12 is a diagram showing trajectories of scanning rays at adistance from the read windows. In this case, examples of scanning raysat a position distanced by 100 mm from the read windows are shown.Compared with the scanning patterns shown in FIG. 11, the scanningpatterns spread widely as a whole. As shown in FIG. 11, the larger thedistance from the read windows is, the more widely the scanning patternsspread. Consequently, even if the position of a bar code passing aposition away from the reader is a position off the center of a readwindow, the probability that the bar code is scanned is high.Eventually, the success rate (read probability) of reading a bar codeimproves.

[0225]FIGS. 13A to 13C are views showing the usages of the reader ofthis embodiment. FIG. 13A shows an example of using the reader as astationary reader. FIG. 13B shows an example of using the reader as agun reader. FIG. 13C shows an example of using the reader as a touchreader.

[0226] For using the reader as a stationary reader, the reader body ismounted on the stand. In this case, the grip of the reader is insertedinto a holder section of the reader is inserted into a holder section ofthe stand. Thus, the reader body is immobilized and the read windowsface in a given direction.

[0227] For reading bar codes in this state, articles bearing bar codesare passed with the bar codes opposed to the read window employed. Asalready described, a scanning pattern 10 permitting scanning in aplurality of directions is supplied through the first read window. Thescanning rays scan a wide range. As shown in FIG. 13A, a bar code isscanned by numerous scanning rays having different inclinations. Forreading bar codes using the stationary reader, the inclinations of thebar codes passing the read window are not constant as long as a user isnot especially conscious of them. However, since a bar code is scannedusing the above scanning pattern, even if a bar code passing the readwindow employed is tilted, the possibility that the bar code is scannedby any of the scanning rays is high.

[0228] For using the reader as a gun reader, as shown in FIG. 18B, auser holds the grip and directs the read window employed toward abar-code surface located at a far position. The bar-code surface is thenscanned using the scanning pattern. When the reader is used as a gunreader, bar codes are often at a distance from the read window.Similarly to those scanned by the stationary reader, the bar codes donot have a constant inclination. In particular, bar codes supposed to beread by a gun reader include those located beyond one's reach and thosecarried by heavy articles. In some cases, the orientations of bar codescannot be changed. Even when the reader is used as a gun reader, thescanning pattern supplied through the first read window is used to readbar codes. The scanning pattern spreads more widely as it gets fartherfrom the read window employed. If the read window employed is only aimedroughly at a bar code, the desired bar code can be scanned.

[0229] For using the reader as a touch reader, as shown in FIG. 13C, auser holds the grip of the reader body. The second read window is thenbrought to the position of a specific bar code on, for example, abar-code menu. A scanning ray emitted through the second read window isused to scan the bar code that is an object of reading. The scandirection of the scanning ray emitted through the second read window isfixed. Since the bar-code menu is placed near the user's hand, it iseasy to align the bar code.

[0230] When the scanning pattern supplied through the second read windowis made different from that supplied through the first read window sothat mutually-intersecting scanning rays to be scanned in manydirections will not be produced, the scan range of the scanning rayemitted through the second read window is a quite limited range. Forexample, when a scanning ray that is emitted through the second readwindow is only the one scanned in one direction as shown in FIG. 10, thescanning pattern supplied through the second read window merely enableshorizontal and linear scanning of a scan surface.

[0231] A bar code is in principle long sideways. When scanned in adirection along the shorter edges of a bar code, the bar code cannot beread. A scanning ray emitted through the second read window is thereforedesigned to be scanned in one direction. Consequently, a bar code thatis not an object of reading or any other unwanted area will not bescanned. Reading an unwanted bar code or an incidence posing a problemwhen a bar-code menu is read can be avoided.

[0232] When the reader is used as a touch reader, it is possible toalign the inclination of a bar code with the read window employed.Scanning rays having different scan directions are thereforeunnecessary. When the reader is used as a touch reader, therefore, onescanning ray emitted through the second read window and scanned in onedirection is used to read bar codes.

[0233] A scanning ray has a minimum diameter at a focal position. Thesmaller the diameter is, the thinner the readable bars of a bar codeare. When a bar code is located at (or in the vicinity of) the focalposition of a scanning ray, even if the bar code consists of thin bars,reading succeeds. It is therefore preferable that a position at which ascanning ray is focused be in the vicinity of the position of a bar codeto be read in each read form.

[0234] When the reader is used as a stationary or gun reader, bar codespass a position away from the read window employed. It is thereforepreferable that the focal position of scanning rays emitted through thefirst read window be a position away from the read window, for example,a position several tens of centimeters away therefore. For a larger readrange, it is required that a readable area is realized ahead and behindthe read window. Consequently, a read depth permitted by scanning raysemitted through the first read window should preferably be large.

[0235] When the reader is used as a touch reader, a bar code is locatedvery close to the read window employed. It is therefore preferable thatthe focal position of a scanning ray emitted through the second readwindow be on or near the second read window. Moreover, since the spacingbetween a bar code and the read window is not so large, the read depthof a scanning ray emitted through the second read window may be small.

[0236] When the reader is used as a touch reader, if the read depth ofscanning light emitted through the second read window is large, a barcode located at a position away from the second read window is alsoscanned. In this case, the possibility of reading a bar code that neednot be read is high. For reading a bar-code menu, especially, while thereader is being moved to a desired bar code, it passes over the otherbar codes recorded on the menu sheet. At this time, there is apossibility that the scanning light may scan the other bar codes andread them. The bar codes recorded on the menu sheet are valid datairrespective of whether or not they are objects of reading. While thereader is being moved, if unnecessary bar codes are read, unwantedinformation is input to cause a problem.

[0237] For preventing the occurrence of a problem, it is preferable thatthe read depth of scanning light emitted through the second read windowbe small.

[0238]FIG. 14 is a view showing a variant of the reader of thisembodiment. A reader shown in FIG. 14 has, unlike the reader shown inFIG. 6, the first read window and second read window thereof angleddifferently.

[0239] Scanning light emitted through the first read window is emittedhorizontally or slightly downward in FIG. 14 with the read windowdirected substantially in a vertical direction. When the reader ismounted on the stand, it is preferable, in consideration of the heightof the read window and a position at which an article bearing a bar codepasses, that the scanning light emitted through the first read window beangled slightly downward.

[0240] In contrast, the emission direction of scanning light emittedthrough the second read window is obliquely up.

[0241] A conventional touch reader uses an LED as a light source toilluminate the whole of a range having almost the same size as a readwindow. To use the conventional touch reader, a user should merely aimat a proper position so as to put the read window employed in thevicinity of a bar code. The bar code is then illuminated entirely bylight emanating from the LED, and can be read.

[0242] However, in the case of the reader of this embodiment, what isemitted through the second read window is a linear scanning ray (laserlight) alone. A range illuminated by the scanning ray is linear. In thiscase, unless a bar code is placed exactly at a position at which thescanning ray passes, the bar code will not be scanned by the scanningray and cannot be read. For reading an intended bar code correctly,therefore, it is important to locate a position at which a scanning rayscans and a position of a bar code and to align a read window with thebar code.

[0243] When a user's line of vision and an emission direction ofscanning light emitted through the second read window are coincidentwith each other and a bar code lies on an extension of the emissiondirection of scanning light, it is easy to align the read window withthe bar code. When the reader is used as a touch reader (in particular,when a bar-code menu is placed on a tabletop), a bar code that is anobject of reading is located obliquely ahead of a user. For reading abar-code menu, a user is thought to bring the reader into obliquecontact with the bar code for reading. The reader of this embodiment isrealized from this viewpoint. The emission direction of scanning lightemitted through the second read window is, as illustrated, obliquely up.A user can therefore easily aim at the position of a bar code. Theemission direction of scanning light emitted through the second readwindow and a user's line of vision can be coaxially coincided with eachother.

[0244] In the case of FIG. 14, three scanning rays having differentinclinations are emitted through the first read window. One scanning raypermitting a large scan width is emitted through the second read window.Incidentally, the number of scanning rays is not limited to the oneshown in FIG. 14.

[0245]FIG. 15 is a four-side view of the reader shown in FIG. 14. A planview is seen in the left upper area in the drawing, a side view is seenin the left lower area, a back view is seen in the right lower area, anda top view is seen in the right upper area. A cover 14 molded using amember having elasticity, for example, rubber is attached to theperimeter of the second read window. When the second read window is usedto read a bar code, the cover prevents the second read window fromcoming into direct contact with a surface bearing a bar code or the likeand being flawed. Moreover, the cover absorbs impact occurring when theread window is brought into contact with the bar-code surface. Inaddition, the cover exerts the operation of a spacer for separating abar code and the second read window optimally for reading of the barcode. When this kind of cover is attached, a bar code that is an objectof reading is located around the tip of the cover. Consequently, thefocal position of scanning light emitted through the second read window(a position at which the scanning light is focused) should preferably bethe position of the tip of the cover or a position slightly ahead of thetip.

[0246] Indicators 16 a and 16 b for notifying a user of whether or not abar code has been read normally are located on the upper margin of thesecond read window and on the back side of the reader respectively. FIG.14 shows an example in which an indicator 16 b is located on the cover14 attached to the perimeter of the second read window. An indicator onthe back side is not shown.

[0247] The indicators 16 a and 16 b are lit when a bar code is readnormally or reading a bar code fails, whereby a user is notified of abar-code reading situation.

[0248] Another mechanism for notifying a bar-code reading situation is aspeaker for giving a reporting sound.

[0249] Moreover, a mode selection switch 15 b is located on the backside of the reader. The operation of the mode selection switch will bedescribed in detail later. In short, the mode selection switch is usedto change a read mode in which a bar code is read using scanning lightemitted through the first read window into a read mode in which a barcode is read using scanning light emitted through the second readwindow, or vice versa.

[0250] A cable is coupled with the rear end of the grip, though it isnot shown in FIG. 15.

[0251]FIG. 16 is a view showing a state in which the reader shown inFIG. 14 is mounted on the stand and used as a stationary reader. Whenthe reader is used as a stationary reader, a scanning pattern (Amulti-scanning pattern. Scanning using the multi-scanning pattern isreferred to as multi-scanning.) being supplied through the first readwindow and permitting scanning in a plurality of directions is sued toscan bar codes. In this case, when the reader is placed to have such apositional relation that it is opposed to a user, scanning light isemitted toward the user through the read window. When the reader is thusplaced, the maneuver for reading can be achieved readily.

[0252] Moreover, since the range scanned using a scanning patternsupplied through the first read window 13 a 10 c is wide, when a barcode 4 passes through a scan area 10 c, the bar code can be read. When auser intends to have a bar code read, he/she need not be so greatlyconscious of a position at which an article 100 is passed. The wider thescan area is, the greater is the freedom of setting a position as anarticle passes.

[0253] Incidentally, a dent 5 for guiding the cable 3 coupled with theend of the grip to the forward side of the stand is formed on the baseof the stand.

[0254]FIG. 17 is a view showing an example of using the reader as a gunreader. When the reader is used as a gun reader, a user holds the gripand directs the first read window toward a bar code borne by an article.Even in this case, multi-scanning is performed for reading. This usageis suitable for a case in which it is hard to match the position of abar code with a specific direction.

[0255]FIG. 18 is a view showing a case in which the reader shown in FIG.14 is used as a touch reader. In the case shown in FIG. 18, the readeris brought to the position of a specific bar code on a bar-code menu 4.The bar code that is an object of reading is thus approached to thesecond read window. The reader shown in FIG. 14 has the second readwindow slightly inclined relative to the first read window. The secondread window faces slightly up. For reading a bar code, the bar-code menuis often placed on a desk or the like for reading. The reader is heldover the bar-code menu. When the second read window is inclined as shownin FIG. 14, and when the second read window approaches a bar code, thesecond read window can be bought into contact with the bar code in anatural manner.

[0256] As already described, the reader is provided with indicators,such as LEDs, that, when reading a bar code has completed normally,notify a user of the fact. When the reader is used as a stationaryreader, the user is opposed to the read window. For the use of thereader as a stationary reader, therefore, an indicator should be formedon a read window so that it can be discerned easily.

[0257] When the reader is used as a hand-held reader, a user cannotdiscern the read window but can merely see the back side of the reader.If an indicator were located only on a read window, the user using thereader as a hand-held reader would have difficulty in discerning theindicator. However, since another indicator is located on the back sideof the reader, the user can discern the indicator even when using thereader as a hand-held reader.

[0258] In the reader shown in FIG. 14, an indicator is located on eachof the read window and the back side of the reader, so that the litstate of an indicator can be checked from either the front or back sideof the reader. As for the indicators, different indicators may be placedon the front and back side of the reader respectively. A light source(LED or the like) for indication may be shared by the indicators. Lightemanating from the LED may be guided to the front and back sides so thatthe plurality of indicators can be lit simultaneously. For reducing thenumber of parts, the same light source should preferably be shared.

[0259]FIG. 19 is a diagram showing the structure of the indicatorssharing the same LED light source. In the case shown in FIG. 19, an LEDlight source 5 is placed on the back side of the reader. A clear member53 made of a resin or the like is located ahead of the LED light source.

[0260] When light is passed through a transparent member, if the angleof incidence of the light incident to a wall of the member is equal toor smaller than a critical angle, the incident light is reflected fully.If the angle of incidence of the light is larger than the criticalangle, the incident light is emitted outside from the wall of themember.

[0261] The indicators shown in FIG. 19 are realized by making the mostof the foregoing nature of light.

[0262] One end of the clear member is, as mentioned above, provided withthe LED light source 51, and the other end thereof serves as theindicator 16 b located on the second read window 13 b. An opalescentmember 52 is placed at an end of the clear member 53 in the vicinity ofthe LED light source 51, whereby the indicator 16 a on the back side ofthe reader is materialized.

[0263] Light emanating from the LED light source enters the clear member53. Light entering the wall of the clear member at an angle equal to orsmaller than the critical angle is guided to the indicator 16 b locatedon the second read window 13 b. Thus, the indicator on the second readwindow is illuminated.

[0264] By contrast, light emanating from the LED light source 51 andentering the wall of the clear member at an angle equal to or largerthan the critical angle passes through the clear member and is emittedoutside. The opalescent member is located at a position at which lightemanating from the LED light source is emitted outside. Light emanatingfrom the LED light source is therefore emitted directly through theopalescent member, whereby the indicator on the back side of the readeris illuminated. The opalescent member acts as a plane of diffusion andscatters light emanating from the LED light source. A user can thereforediscern the contents of indication made by the indicators in a widerange.

[0265] Owing to the foregoing structure, the common LED light source 51is used to allow the indicators 16 b and 16 a located on the front andback sides of the reader to make indication for notifying a bar-codereading situation.

[0266]FIGS. 20A and 20B are views showing the stand on which the readeris mounted. The reader is in the same as the reader shown in FIG. 16.FIG. 20A is an oblique view and FIG. 20B is a side view.

[0267] As already described, the grip 12 of the reader is inserted intothe holder section 62 of the stand. Thus, the reader 1 is fixed to thestand 2. Since the cable 3 is extending from the bottom of the reader, anotch 63 is formed on the front side of the holder section for fear thecable 3 may interfere with mounting or dismounting of the reader on orfrom the stand 2.

[0268] For using the reader as a stationary reader, the reader ispositioned so that the read window thereof will be opposed to a userwith a counter or the like between them and scanning light will beemitted toward the user. This layout facilitates the work of bar-codereading. By contrast, for using the reader as a hand-held reader, thereader must be dismounted from the stand and drawn close to the user.

[0269] In consideration of the foregoing usages, it is required to forma notch, through which the cable of the reader can be led out, on theholder section of the stand for fear the cable may interfere withmounting or dismounting of the reader on or from the stand. From theviewpoints of the position of the reader used as a stationary reader andof the work of mounting or dismounting the reader on or from the stand,the notch should preferably be formed on the front side of the holdersection facing a user.

[0270] Moreover, a dent 4 is formed on the base of the stand so that itwill extend from under the holder section of the stand toward the userside. When the reader is mounted on the stand, the cable lies in thedent. The cable can thus be led into the user side. The cable coupledwith the end of the grip cannot be bent very sharply. Forming the denton the base of the stand is therefore effective in the sense ofprotecting the cable.

[0271] The holder section is pivotable in arrow directions in FIGS. 20Aand 20B relative to the base of the stand. The read window employed ofthe reader and the emission direction of scanning light emitted throughthe read window can be set at a desired angle. As shown in FIG. 20B, theemission direction of scanning light emitted through the read windowemployed can be adjusted freely within the pivotable range of the holdersection.

[0272]FIG. 21 is a three-side view of the stand on which the reader ofthis embodiment is mounted. In FIG. 21, a top view is seen in the leftupper area, a front view is seen in the left lower area, and a sidesectional view is seen in the right upper area. The holder section ofthe stand is supported at two points by the base. The points serve asfulcrums. The dent formed on the base has a shape spreading toward theedge of the base. The tip of the holder section is made wider so thatthe end of the grip of the reader can be introduced readily.

[0273] The stand shown in FIG. 21 is made of, for example, a resin.

[0274] A spring is located at one of the fulcrums of the holder section.A locking member 624 is attached to the other end of the spring. A platesuch as a metallic plate is screwed to the bottom of the base. Thesecomponents will be described in detail later.

[0275]FIG. 22 is a four-side view showing a state in which the reader ismounted on the stand. In FIG. 22, a back view is seen in the left upperarea, a side view is seen in the left lower area, a front view is seenin the right lower area, and a top view is seen in the right upper area.As shown in FIG. 22, when the reader 1 is mounted on the stand 2, Theread windows (especially the first read window) can be placed at properheights and fixed in desired directions. The reader is merely insertedinto the holder section of the stand and locked in the holder sectionowing to its own weight. The work of mounting or dismounting the readeron or from the stand (especially dismounting) can be achieved readily.

[0276]FIG. 23 is a view showing adjustment of an angle at which theholder section of the stand is set. In the case shown in FIG. 23, theright hand of the drawing is the user side. FIG. 23 shows three states;a state in which the reader is mounted upright, a state (a) in which thereader is tilted toward the user side to the greatest extent and thefirst read window faces down, and a state (b) in which the reader istilted toward the side opposite to the user side to the greatest extentand the first read window faces fully up.

[0277] As shown in FIG. 23, the angle of the reader can be adjustedfreely within a range from a position a to b. The reader can be set atan optimal angle according to the installation site of the reader or theusage of the reader.

[0278] The stand can not only be placed on a counter but also, forexample, be hung on a wall. When the stand is hung on a wall, the readeris immobilized at the position b in FIG. 23.

[0279] In case the wall has a metallic surface, a magnet or the like maybe attached to the bottom of the stand so that the stand can beattracted to the wall. When the wall does not have the metallic surface,the stand is hung as described below.

[0280] As shown in FIG. 21, a screw hole 601 is formed around the centerof the stand base. The screw hole is used to screw the stand 2 to awall. The stand can thus be hung on the wall. However, when the stand issupported at only one point, there is a possibility that the standrotates with the screwed point as a center. The stand cannot thereforebe fixed to the wall on a stable basis.

[0281] A method of preventing the rotation of the stand is a method inwhich a plurality of screw holes are formed in the stand. If this methodwere adopted, since the stand is fixed at the plurality of points, thestand will not rotate. However, since numerous holes are bored in thestand, the appearance is not good.

[0282] A plate 611 such as a metallic plate is therefore, as shown inFIG. 19, attached to the bottom of the stand base of this embodiment.The plate may have, for example, a round shape. The shape of the plateis not limited to the one shown in FIG. 24. Supposing the plate is ametallic plate, since the plate has weight, it fills the role of aweight. When the reader is mounted on the stand, since the center ofgravity of the stand can be lowered, the stand becomes stable.

[0283] A part A of the plate 611 is molded in line with the shape of thebase 61 of the stand 2. Normally, the plate 611 will not come out of thestand 2. The plate 611 and stand 2 are secured with two screws. A screwhole used to fix the plate and bored in the stand is shown even in thefront sectional view of FIG. 21.

[0284] The plate has three holes along the same line. In the state shownin FIG. 24, that is, in a normal state, a hole c in the center of theplate coincides with the position of a screw hold 601 in the stand base.Two screw holes are formed intermediately between the center hole c anda hole a in the plate.

[0285] For hanging the stand on a wall, as shown in FIG. 25, the plateis turned upside down relative to the state shown in FIG. 24. An upperview in FIG. 25 is a view of the back side of the plate, and a lowerview therein is a view of the lateral side thereof. In this state, thehole a of the plate coincides with the screw hole of the stand base. Thehole b of the plate comes out of the stand.

[0286] For hanging the stand on a wall, the hole b of the plate and thehole of the stand base (hole a of the plate) are used to attach screws.The stand is thus fixed to the wall. FIG. 26 is an oblique view showingthe work of attachment. FIG. 27 is a side sectional view showing thestand 2 in a state in which the stand 2 is hung on a wall 150. As shownin these drawings, in this embodiment, the stand is screwed at twopoints. The stand will not rotate when hung on a wall. Moreover, thework of screwing the plate can proceed smoothly.

[0287] Without a mechanism for stopping the pivoting of the holdersection, there is a possibility that when the reader is angled evenslightly, it is turned to the position a in FIG. 23 because of theweight of the reader and other factors. The stand in this embodiment istherefore provided with a mechanism for controlling the pivoting of theholder section in a multistage fashion and for stopping the pivoting ofthe holder section.

[0288]FIG. 28 is an explanatory view concerning a tilt mechanism. FIG.29 is a side perspective view showing the major portion of the standhaving the tilt mechanism in enlarged form. FIG. 30 is a front view ofthe major portion. A supporting member 622 having a plurality of teethin an arc form is fixed to the base of the stand. A spring 623 islocated at one of the fulcrums of the holder section. The other end ofthe spring is attached to a locking member 624 that is shaped to meshwith the teeth of the supporting member fixed to the base. The lockingmember is constrained to go toward the fulcrum because of the elasticityof the spring.

[0289] Since the tilt mechanism is employed in the stand, when theholder section is pivoted, the teeth of the supporting member are meshedwith the teeth of the locking member. The supporting member isconstrained to go toward the fulcrum due to the elasticity of thespring. The holder section 62 can therefore be locked in a pivotedstate. Consequently, a multi-stage angle adjustment can be realized.

[0290]FIG. 29 shows the cable 3 led out from the bottom of the reader.The cable is bent toward the read-window side of the reader so that thecable can be led out to the user side without fail when the reader ismounted on the stand.

[0291] As mentioned above, when the reader is mounted on the stand, thereader can be used as a stationary reader. If necessary, the reader canbe dismounted from the stand and used as a hand-held reader.

[0292] For using the reader as a hand-held reader, a user holds the grip12. When the reader is mounted on the stand, the grip of the reader isinserted into the holder section. For dismounting the reader from thestand, it is impossible to hold the grip and dismount the reader. Unlesshands are changed, the grip cannot be held. For dismounting the readerfrom the stand, the head must be held. The head is larger than the gripand hard to hold with a hand. Especially, a user having small hands maynot be able to raise the head with one hand. Thus, there is a problemthat the work of dismounting the reader from the stand is troublesome.

[0293] In order to solve this problem, the grip is designed to be heldwith the reader mounted on the stand.

[0294]FIG. 31 shows a stand proposed to solve the problem. In FIG. 31, alaying stand 64 is attached to the stand that has been described so far.The laying stand has a tongue 65 on the bottom thereof. The tongue isinserted into the holder section. The laying stand 64 is attachable anddetachable to and from the stand body. When needed (for laying thereader), the laying stand is attached to the stand body. When not needed(for erecting the reader), the laying stand is detached from the standbody.

[0295]FIG. 32 is a view showing a state in which the reader is mountedon the laying stand. The reader 1 is laid on the laying stand shown inFIGS. 31 and 32. Specifically, the head 11 of the reader 1 is placed onthe laying stand. Even in this case, no special mechanism is needed inorder to fix the head of the reader to the laying stand. The reader 1 ismerely locked on the laying stand owing to its own weight.

[0296] However, when the reader is laid, the grip comes out sideways.The reader cannot be laid on the laying stand on a stable manner when nomeasure is taken. The laying stand is therefore provided with threewalls 641, 642, and 643 for supporting the head. The right and leftwalls 641 and 642 of the laying stand support the lateral side of thehead 11 of the reader ad part of the front side of the head 11. The wall643 formed at the deep end of the laying stand supports the back side ofthe head 11 of the reader. Owing to these walls, the orientation of thefirst read window 13 a of the reader is defined. The first read windowcan be directed toward the user side. Furthermore, it can be preventedthat the reader falls off the laying stand.

[0297] In FIG. 32, the grip of the reader is located on the right hand.Thus, the grip is not inserted into the stand but comes out of thestand. A user can therefore hold the grip readily. The reader can bedismounted from the stand with the grip thereof held.

[0298] The laying stand has a symmetric shape. As shown in FIGS. 33A and33B, the grip can be placed on either the right or left hand. FIG. 33Ashows a state in which the grip is placed on the left hand (relative toa user). FIG. 33B shows a state in which the grip is placed on the righthand (relative to a user). FIG. 33B shows the walls supporting the frontside of the head, while FIG. 33A does not show the walls for betterunderstanding of the state of the head on the laying stand.

[0299] As shown in FIGS. 33A and 33B, the grip 12 of the reader 1 can beplaced on either the right or left hand. Depending on whether a user isright-handed or left-handed, the orientation of the grip of the readerthat is laid on the stand can be selected freely.

[0300] When intending to have a bar code read, a user tends to pass thebar code intentionally horizontally or vertically by the read windowemployed. Moreover, a bar code is printed lengthwise on, for example, acan. Thus, in many cases, the width or length direction of an articlebearing a bar code agrees with the longitudinal direction of the barcode. It may be a matter of course in terms of the user's way ofmaneuvering the reader that the probability that the orientation of abar code passing the read window is a horizontal or vertical directionis high.

[0301] when the reader is used as a stationary reader in order to read abar code, although the angle of the bar code need not concern the user,it is preferable in consideration of the aforesaid point that thescanning pattern supplied from the read window employed includes asubstantially horizontal or vertical scanning ray.

[0302] When the reader is mounted on the laying stand, it is angled sothat at least one scanning ray constituting the scanning patternsupplied from the first read window scans horizontally. Moreparticularly, as shown in FIGS. 33A and 33B, the reader is placed sothat the grip 12 of the reader 1 slightly slants down. When the readeris angled this way, one of scanning rays constituting the scanningpattern is scanned horizontally.

[0303] Likewise, the reader is placed so that one of the scanning raysconstituting the scanning pattern supplied through the first read window13 a is scanned vertically.

[0304] Since the scanning pattern thus includes horizontal and verticalscanning rays, the horizontal or vertical orientations of bar codes,with which the bar codes are passed at a high probability, agree withthe scan directions of the scanning rays. Reading bar codes can beachieved more reliably.

[0305]FIGS. 34 and 35 are views showing the reader erected on the standin comparison with the reader laid on the stand. FIG. 34 shows anerecting stand, while the FIG. 35 shows a laying stand.

[0306] As shown in FIG. 34, when the erecting stand is used, the grip 12is inserted into the holder section. The reader mounted on the stand isstable. However, it is hard to dismount the reader from the stand byholding the grip. The work of mounting or dismounting the reader israther hard to do.

[0307] As shown in FIG. 35, when the laying stand is used, since thegrip of the reader is easy to hold, the work of mounting or dismountingthe reader can be carried out efficiently. In particular, when thereader is used as a hand-held reader, it becomes unnecessary to changehands. However, since the grip is coming out sideways, it is hard tobalance the weight of the reader. The reader mounted on the stand doesnot become stable immediately.

[0308] A user is therefore requested to select the erecting stand orlaying stand by taking account of the usage of the reader and the meritsand demerits of the stands.

[0309] When the reader is used as a stationary reader or gun reader, thescanning pattern supplied through the first read window 13 a is used toperform multi-scan. The scanning light emitted through the second readwindow 13 b is not directly involved in reading of bar codes.

[0310] As shown in FIGS. 9 and 14, the supply direction of the scanningpattern through the first read window 13 a is different (has a differentangle) from the emission direction of the scanning light through thesecond read window 13 b. If scanning light is emitted through both thefirst and second read windows, in case the reader is used as astationary or gun reader, when the scanning pattern supplied through thefirst read window is directed toward a bar code that is an object ofreading, the scanning light emitted through the second read windowtravels in a direction completely different from the direction towardthe bar code that is an object of reading, and therefore scans somethingthat has not relation to the bar code.

[0311] There is a possibility that light reflected from anything otherthan a bar code that is an object of reading, which has been scanned bythe scanning ray emitted through the second read window, may be detectedby the reader. This results in noise or incorrect recognition by thereader. In this case, the reader causes a read error.

[0312] By contrast, when the reader is used as a touch reader, thescanning pattern supplied through the first read window is not used forbar-code reading. However, as shown in FIG. 13C, even when the scanningray emitted through the second read window is used to read a bar code ona bar-code menu, if scanning rays are still emitted through the firstread window, a bar code that is not an object of reading is scanned bythe scanning rays emitted through the first read window. The reader thendetects both reflected light of the scanning rays emitted through thefirst read window and reflected light of the scanning rays emittedthrough the second read window.

[0313] In case the both kinds of reflected light contain bar-code datathat is valid data, the reader cannot distinguish which is wanted data.In particular, since all bar codes recorded on a bar-code menu are validdata irrespective of whether the data is or is not required to be input,two different bar codes coexist. This leads to a problem that doublebar-code read occurs. In this case, since it is impossible to input therequired information alone, the input information must be erased or datamust be input again.

[0314] In order to solve the foregoing problem, according to a read formof the reader, it is required to substantially invalidate bar-codereading based on scanning light emitted through a read window notassociated with the read form during, for example, a period during whichthe scanning light is emitted through the read window not associatedwith the read form.

[0315]FIG. 36 is a view showing part of a polygon mirror. A structurefor use in locating a position scanned by a scanning ray is shown. Adisk-like member 222 having a plurality of slits is placed on the baseof the polygon mirror 22. A sensor 221 for detecting the passage of aslit is mounted on the base on which the polygon mirror is placed. Whendetecting passage of a slit, the sensor 221 outputs a mirror positiondetection signal.

[0316] One of the slits formed on the disk member 222 has a larger widthin order to indicate a reference polygon position. The sensor is used todetect the slit indicating the positional reference, whereby a controlunit of the reader, which is not shown, recognizes that a specificsurface of the polygon mirror has passed the sensor position. Thus, thecontrol unit grasps the rotated state of the polygon mirror, and judgesto which floor mirror scanning light is incident.

[0317] When the reference position is set to a specific position of thepolygon mirror, it can be recognized that the specific position of thepolygon mirror has passed the sensor position. By counting the number ofslits passed after the detection of the reference position, it can bechecked readily which surface of the polygon mirror has passed thesensor position.

[0318]FIG. 37 shows the waveform of an output of the sensor shown inFIG. 36 and the waveform of a mirror position detection signal based onthe output. FIG. 37 shows the sensor output and mirror positiondetection signal. In FIG. 37, (1) is associated with the firstreflection surface, (2) is associated with the second reflectionsurface, (3) is associated with the third reflection surface, and (4) isassociated with the fourth reflection surface.

[0319] Furthermore, in FIG. 37, reference numerals 23-1 to 23-8 denotethe floor mirrors to which scanning light reflected from the respectivereflection surfaces is incident and which correspond to the floormirrors shown in FIG. 7A. Herein, although “23-1 to 23-5” is written inFIG. 37, when the polygon mirror is rotating clockwise in FIG. 7A, theactual scanning order is the floor mirrors 23-3, 23-2, 23-1, 23-5, and23-4.

[0320] The sensor output shown in FIG. 17 is driven on every time a slitis detected, and driven off for the other things. The duration duringwhich the output is on is comparable to the width of a slit. As shown inFIG. 37, the wide slit serving as a positional reference is formed sothat it will be detected when scanning light reflected from the firstreflection surface starts scanning the floor mirrors 23-1 to 23-5(actually the floor mirror 23-3).

[0321] When the wide slit is detected, the on duration of the sensoroutput is long. The control unit of the reader which is not shownrecognizes that the scanning light reflected from the first reflectionsurface of the polygon mirror has started scanning the floor mirror23-3.

[0322] The number of slits formed on the disk member is predetermined.It is also predetermined which slit is associated with which position ofwhich reflection surface of the polygon mirror. Once the positionalrelationships of the reference slit passing the sensor with thereflection surfaces of the polygon mirror are pre-set in the controlunit or the like, the control unit can readily grasp which reflectionsurface of the polygon mirror is reflecting light and which floor mirroris being scanned by the reflected light by counting the number of slitsthat have passed the sensor after the detection of the reference slit.The control unit then recognizes the period during which scanning lightreflecting from the fourth reflection surface of the polygon mirror isscanning the floor mirror E8, and, as shown in FIG. 37, retains themirror position detection signal in the one state during the period.

[0323]FIG. 38 is a functional block diagram of the reader. In FIG. 38,reference numeral 221 denotes a sensor mounted on the base of thepolygon mirror. The sensor 221 detects a slit 223. 225 denotes a controlunit for controlling the operations of the reader. 226 denotes a counterfor counting the number of outputs of the sensor 221. 21 denotes a laserdiode serving as a light source. 227 denotes a light detection circuitfor detecting light reflected from a bar code. The operations of thelaser diode 21 and light detection circuit 227 are controlled by thecontrol unit 225.

[0324] Furthermore, reference numeral 224 denotes a mode selectionswitch. The reader has two read modes: a first read mode (multi-scanningmode) in which a scanning pattern composed of a plurality of scanningrays emitted through the first read window is supplied, and a secondread mode (single-scanning mode) in which one scanning ray is emittedthrough the second read window. A user manipulates the mode selectionswitch when he/she needs it, whereby the first read mode and second readmode can be changed. Thus, the user can designate a desired read mode.

[0325]FIG. 39 is a flowchart describing read mode change achieved bymanipulating the mode selection switch. The control unit always monitorsif the mode selection switch has been manipulated (step 901). When themode selection switch is not manipulated, the read mode is regarded asthe multi-scanning mode (step 903) and the light source is controlled sothat scanning light will be emitted through the first read window.

[0326] In contrast, when it is detected that the mode selection switchhas been manipulated, the control unit changes the read mode into thesignal-scanning mode and controls lighting of the light source so thatscanning light will be emitted through the second read window alone(step 902).

[0327] Based on the thus-selected read mode, bar-code reading isexecuted.

[0328]FIG. 40 is a flowchart describing how to control lighting of thelight source more particularly.

[0329] What is needed in multi-scanning mode is scanning light emittedthrough the first read window 13 a. Scanning light reflected from thefloor mirror 23-8 is not needed to read bar codes. By contrast, what isneeded in single-scanning mode is only the scanning light emittedthrough the second read window 13 b. Only the scanning light reflectedfrom the floor mirror 23-8 is needed and the other scanning light is notneeded.

[0330] When the read mode is set to single-scanning, the control unitoperates the laser light source only during a period during which lightreflected from the polygon mirror is scanning the floor mirror 23-8(step 907), and reads a bar code. By contrast, when the read mode is setto the multi-scanning mode, the control unit does not operate the laserlight source during a period during which the floor mirror 23-8 isscanned (step 908), and reads a bar code.

[0331] Owing to the foregoing lighting control, scanning light can beemitted only through the read window associated with each read mode.

[0332]FIG. 41 shows the waveforms of outputs of the components shown inFIG. 38.

[0333] An output from the mode selection switch is fed to the controlunit. For selecting the first read mode (for emitting scanning lightthrough the first read window 13 a), the output is driven off. Forselecting the second read window 13 b), the output is driven on. Thecontrol unit checks the output of the mode selection switch to see whichread mode is selected. Depending on the result, the control unitcontrols lighting of the laser diode.

[0334] The mirror position detection signal is identical to the oneshown in FIG. 37, and remains on during a period during which lightreflected from the fourth surface of the polygon mirror is scanning thefloor mirror 23-8.

[0335] During a period during which the mode selection switch remains onbecause a user intends to use the reader in second read mode or as atouch reader, scanning light is emitted through the second read window13 b but scanning light must not be emitted through the first readwindow 13 a. For a period during which the mirror position detectionsignal remains on, the control unit gives control so as to light thelaser light source. For a period during which the mirror positiondetection signal remains off (the floor mirrors 23-1 to 23-7 are beingscanned), the control unit gives control so as not to operate the laserlight source. Thus, laser light is emitted only through the second readwindow 13 b. When the reader is used as a touch reader in order to reada bar-code menu, it can be prevented that scanning light emitted throughthe first read window scans an unrelated bar code to cause a doubleread.

[0336] When a user uses the reader as a stationary or gun reader, theoutput of the mode selection switch is driven off. Based on this fact,for a period during which the mirror position detection signal remainsoff, the control unit operates the laser light source. For a periodduring which the mirror position detection signal remains on (scanninglight reflected from the fourth reflection surface of the polygon mirroris scanning the floor mirror 23-8), the control unit does not operatethe laser light source.

[0337] Owing to the foregoing control, even when the reader is used as astationary or gun reader, it can be prevented that scanning light isemitted through the second read window 13 b. It can be prevented thatany unrelated thing other than a bar code is scanned.

[0338]FIG. 42 is a view showing an example of a mode selection switch.FIG. 42 shows the back side of the reader. The reader of the embodimentshown in FIG. 42 has a mode selection switch 15 d on the back sidethereof. The mode selection switch 15 d is manipulated by the indexfinger or thumb of a user's hand holding the grip.

[0339] It is required to form the mode selection switch at a positionpermitting easy manipulation by a finger of a hand holding the grip. Inparticular, either a person having large hands or a person having smallhands must be able to manipulate the mode selection switch in the samemanner.

[0340] The mode selection switch is formed even on, for example, thereader shown in FIG. 15. In the case shown FIG. 15, the mode selectionswitch 15 b is shaped like a letter V. Owing to the shape like a letterV, the mode selection switch can be made long and wide.

[0341] The position on the switch at which the finger is rested variesdepending on whether the switch is manipulated by an index finger or bya thumb. However, since the mode selection switch is made long, eitherthe index finger or thumb can press the mode selection switch. Since themode selection switch is made wide, either a person having long fingersor a person having short fingers can manipulate the mode selectionswitch in the same manner.

[0342]FIG. 43 is a view showing a state in which the mode selectionswitch (function change switch) is pressed by an index finger. In thiscase, a user holds the grip with all his/her fingers except the indexfinger and stretches the index finger. The mode selection switch islocated at a position at which the stretched index finger lies.

[0343] When the grip is held as shown in FIG. 43, the index finger andthumb of a maneuvering person is spaced like a letter V, though itdepends on the person. When the grip is held by a right hand, the indexfinger lies on the right-hand part of the mode selection switch. Whenthe grip is held by a left hand, the index finger lies on the left-handpart of the mode selection switch. Since the mode selection switch ismade wide, as shown in FIG. 43, when the grip is held, the index fingercan be rested on the mode selection switch in a natural manner.Furthermore, whichever of a right hand and left hand is used, the modeselection switch can be manipulated in the same manner.

[0344]FIG. 44 is a view showing a state in which the mode selectionswitch (function change switch) is manipulated by a thumb. In this case,the grip is held by all the fingers except the thumb and the root of thethumb.

[0345] When a thumb is used to manipulate the mode selection switch, thethumb manipulates the root of the mode selection switch mainly.

[0346] As mentioned above, the position of the finger varies dependingon whether an index finger is used to manipulate the mode selectionswitch or a thumb is used thereto. Since the mode selection switch ismade long, the switch can be used for switching by an index finger or bya thumb. Since the mode selection switch is shaped like a letter V, theswitch can be pressed reliably in whatever manner it is manipulated.

[0347]FIGS. 45A and 45B are views showing a V-shaped switch plate. Theswitch plate shown in FIGS. 45A and 45B is supported at three points.Three fulcrums; fulcrums A, B, and C are set at the apices of the switchplate. The apices serving as the fulcrums are inserted into openings,which are not shown, formed in the back side of the reader, and thensupported by juts in the openings. A claw is formed at the tip of eachapex serving as a fulcrum. The claws prevent floating of each apexserving as a fulcrum.

[0348] A switch is incorporated in an area of the reader body coincidentwith the center of the switch plate. When the switch plate ismanipulated, the switch is depressed. Whichever position of the switchplate is manipulated, the depressing section of the switch incorporatedin the reader body can be depressed. Unlike a structure in which aswitch lies at only one point, even a person having small hands willfind it easy to manipulate the switch. The switch plate is constrainedto go slightly upward by means of a spring or the like within theswitch.

[0349]FIGS. 46A and 46B are diagrams for explaining the operation of theswitch plate. Herein, letters A, B, and C denote fulcrums shown in FIGS.45A and 45B. The outline of the switch plate is not shown.

[0350]FIG. 46A shows a state in which a portion of the switch plate inthe vicinity of fulcrum A is manipulated, and FIG. 46B shows a state inwhich a portion of the switch plate in the vicinity of fulcrum B ismanipulated. When the portion of the switch plate in the vicinity offulcrum A is manipulated, the apices serving as fulcrums B and C arefixed. A straight line linking the apices of fulcrums B and C acts as apivot of the switching plate. When the portion of the switch plate inthe vicinity of fulcrum A is manipulated, the switch plate is presseddown with the line linking the apices of fulcrums B and C as a pivot.Thus, the switch is depressed.

[0351] Likewise, when the portion of the switch plate in the vicinity offulcrum B is manipulated, the apices of fulcrums A and C are fixed. Thestraight line linking the apices of fulcrums A and C acts as a pivot ofthe switch plate. The switch plate is pressed down, and the switch isthus depressed.

[0352] As mentioned above, since the switch plate is attached, whicheverportion of the switch plate is manipulated, the switch can be depressed.The mode selection switch can be manipulated in a stable mannerirrespective of the size of a user's hand. The number of fulcrums neednot be three. However, when three fulcrums are set, a pivot (rotationaxis) relative to a pressed point can be determined uniquely. Foractuating the switch most reliably, the structure of the switch platehaving three fulcrums is most effective.

[0353] The switch plate is attached to the reader so that it will notcome out of the back side of the reader. If the switch plate jutted outof the back side of the reader, there would arise a possibility thatwhen the reader is placed on a tabletop with the back side thereoffacing down, the read mode of the reader is changed to one not intendedby a user.

[0354]FIG. 47 is a view showing another function change switch. In thecase shown in FIG. 47, a change switch 15 e for front-side manipulationis located in the vicinity of the root of the grip. The position of theswitch is a position at which an index finger lies when the grip is heldby a hand. The front-side change switch can therefore be manipulated bythe index finger. In particular, the shape of the switch makes itpossible to form the switch at almost the same position as the triggerswitch 15 a of the gun reader shown in FIG. 3. The change switch can bemanipulated easily.

[0355] In the case shown in FIG. 47, the mode selection switch on theback side of the reader is omitted. However, the mode selection switchmay of course be formed on each of the back side and front side of thereader.

[0356]FIG. 48 is a view showing yet another example of a change switch.In the case shown in FIG. 48, side switches are formed on the lateralsides of the head of the reader. The side switches are a side switch 15f located on the left-hand side of the reader and a side switch 15 glocated on the right-hand side thereof.

[0357] When the grip is held by a hand, the thumb and index finger canbe rested on the side switches. When the grip is held by a right hand,the thumb is used to manipulate the side switch 15 f and the indexfinger is used to manipulate the side switch 15 g. The grip is held bythe remaining fingers. When the grip is held by a left hand, the thumband index finger are used to manipulate the opposite switches. Thus, inconsideration of the uses of both the right and left hands formanipulation of a switch, the side switches are located on the lateralsides of the reader respectively. Owing to this layout, the two switchescan be manipulated simultaneously with ease. Needless to say, only oneof the side switches may be manipulated.

[0358] In the case of the reader shown in FIG. 48, since the sideswitches are located on both the lateral sides of the reader. In aneffort to make the most of this structure, the functions of the sideswitches may be varied depending on whether one of the side switches ismanipulated to both thereof are manipulated simultaneously.

[0359] When one of the side switches is manipulated, the side switchacts as a mode selection switch. In this case, it does not countwhichever of the side switches is manipulated.

[0360] When both the side switches is manipulated simultaneously, theside switches do not act as mode selection switches but are assignedcompletely different functions.

[0361] For example, when one of the right and left side switches ismanipulated (it does not count whichever of the side switches ismanipulated), the read mode is changed from one to the other. When theright and left side switches are manipulated simultaneously, specialreading, for example, repetitive input of a product to be read isexecuted.

[0362] The control unit of the reader always monitors the manipulationsituations of the right and left side switches, judges whether both theright and left side switches are manipulated simultaneously or one ofthe side switches is manipulated, and selects processing to be executedon the basis of the result of the judgment.

[0363] In case a plurality of bar codes representing the same kind ofcontents are read, for example, when a plurality of articles areregistered at a time, it is time-consuming to read the bar codes one byone. A reader having a repetitive input function is known.

[0364] For using the repetitive input function, first, a bar code isread. In principle, a repeat input key is manipulated by the number ofarticles of which bar codes must be input. The repeat input key acts asa counter key. The frequency of manipulating the key is counted by thereader, whereby it is judged how many articles are of the same product.

[0365] Using the foregoing repetitive input function, bar codes borne byarticles of the same product need not be read one by one.

[0366] In this embodiment, two kinds of function can be assigned to theside switches by distinguishing simultaneous manipulation of two sideswitches from manipulation of one of the side switches. That is to say,the functions of the side switches are varied depending on whether oneof the side switches is manipulated or both thereof are manipulatedsimultaneously. Thus, the functions of switches such as the capabilitiesof the repeat input key and mode selection switch can be changedaccording to the number of the switches that have been manipulated. Thisleads to a reduction in number of switches or keys.

[0367] For executing reading according to a read mode, herein, readmodes are changed by controlling lighting of the laser light source insuch a manner that when scanning light is emitted through the first readwindow 13 a, scanning light is not emitted through the second readwindow 13 b, and that when scanning light is emitted through the secondread window 13 b, scanning light is not emitted through the first readwindow 13 a. However, read mode change is not limited to this method.

[0368]FIG. 49 is a diagram for explaining read mode change according toanother method. FIG. 49 shows an output of the mode selection switch, amirror position detection signal, and a light detection circuit controlsignal used to control the light detection circuit and sent from thecontrol unit. Even in the case shown in FIG. 49, the internal componentsof the reader are identical to those shown in FIG. 38. Locating a scanposition is carried out by means of the structure shown in FIGS. 36 and37; that is, by counting the number of slits formed on the disk member.

[0369] The light detection circuit control signal is a signal used tocontrol whether the light detection circuit should be actuated orhalted. During a period during which the light detection circuit controlsignal remains on, the light detection circuit operates. During a periodduring which the light detection circuit control signal remains off, thelight detection circuit does not operate.

[0370] In the case shown in FIG. 49, when the mode selection switch isused to select the window 13 b; that is, the single-scanning mode, thecontrol unit drives the light detection circuit control signal on for aperiod during which the mirror position detection signal remains on, anddrives the light detection circuit control signal off for a periodduring which the mirror position detection signal remains off. When thesingle-scanning mode is selected, therefore, the operation of the lightdetection circuit is validated only for a period during which scanninglight is being emitted through the second read window 13 b, andinvalidated for the other periods.

[0371] In single-scanning mode, therefore, even if scanning light isemitted through the first read window 13 a, the light detection circuitdoes not receive light reflected from a bar code or the like. Even if abar code other than a specific bar code that is an object of reading isscanned during the period, a reading operation is scanned during theperiod, a reading operation is substantially invalidated. During theperiod during which scanning light is being emitted through the secondread window 13 b, the operation of the light detection circuit is valid.Bar-code reading is therefore enabled.

[0372] By contrast, in multi-scanning mode, the output of the modeselection switch is off. Based on this fact, the control unit drives thelight detection circuit control signal on for a period during which themirror position detection signal remains off, and thus validates theoperation of the light detection circuit. For a period during which themirror position detection signal remains on, the control unit drives thelight detection circuit control signal off and thus invalidates theoperation of the light detection circuit.

[0373] For a period during which scanning light is emitted through thefirst read window, therefore, the operation of the light detectioncircuit is validated and bar-code reading is enabled. For a periodduring which scanning light is being emitted through the second readwindow, the operation of the light detection circuit is invalidated.Although the scanning light is emitted through the second read window,the light detection circuit does not receive reflected light.

[0374]FIG. 50 is a diagram describing the foregoing control in the formof a flowchart. The control unit first judges a designated read mode(step 911). When the single-scanning mode is selected, the lightdetection circuit is allowed to operate during a period during which thefloor mirror 23-8 is being scanned. In contrast, when the multi-scanningmode is selected, the control unit does not allow the light detectioncircuit to operate during the period during which the floor mirror 23-8is being scanned, but allows the light detection circuit to operateduring a period during which any other floor mirror is being scanned(step 913).

[0375] As mentioned above, when the control operation described in FIGS.49 and 50 is carried out, even if control is not given to operating thelaser diode, a bar-code reading operation can be substantiallyinvalidated for a period during which scanning light is emitted througha read window not associated with a read mode.

[0376] Changing validation of the operation of the light detectioncircuit into invalidation thereof or vice versa may be achieved bychanging the operation of the light receiving device from one to theother or by invalidating the operation of a circuit for processing asignal output from the light receiving device. Incidentally, read datais decoded within the reader. Validation of a decoding operation may bechanged into invalidation thereof or vice versa.

[0377]FIG. 51 is a flowchart describing controlling of the state of adecoding circuit according to a scanning situation. In the case shown inFIG. 51, when determining that the read mode is the single-scanningmode, the control unit allows the decoding circuit to operate during aperiod during which the floor mirror 23-8 is being scanned and to haltduring any other period (step 917).

[0378] By contrast, when determining that the multi-scanning mode hasbeen selected, the control unit invalidates the operation of thedecoding circuit for the period during which the floor mirror 23-8 isbeing scanned, and validates it during any other period (step 918).

[0379] Alternatively, changing validation of the light detection circuitor the like into invalidation thereof or vice versa and controllinglighting or putting out of the laser diode may be effected incombination. This makes it possible to prevent emission of scanninglight through a window not associated with a read mode and to preventextraneous light entering through a read window during the period frombeing detected by the light detection circuit. Consequently, a read modechange operation can be carried out more reliably.

[0380]FIG. 52 is a diagram showing another arrangement for executingread mode change. In the case shown in FIG. 52, a mirror correspondingto the floor mirror 23-8 is not included. The angle of one floor mirror23-1′ (corresponding to the floor mirror 23-1 in FIG. 7) is madevariable depending on the operation of a solenoid 28.

[0381] The solenoid 28 is movable right and left in FIG. 52, and has anarm at the tip thereof. The arm is provided with the floor mirror 23-1′.The angle of the floor mirror 23-1′ is therefore varied with the rightor left movement of the solenoid 28.

[0382] When the floor mirror 23-1′ lies at a first position (indicatedwith solid lines in FIG. 52), scanning light reflected from the floormirror 23-1′ is emitted through the first read window 13 a. By contrast,when the floor mirror 23-1′ lies at a second position (indicated withdashed lines in FIG. 52), scanning light reflected from the floor mirror23-1′ is emitted through the second read window 13 b.

[0383] When the reader is used as a stationary or gun reader, the floormirror is set at the first position. When the reader is used as a touchreader, the floor mirror 23-1′ is set at the second position.Controlling positioning of the floor mirror 23-1′ is performed with themanipulation of the mode selection switch 13 b.

[0384] When the output of the mode selection switch is on; that is, whenthe single-scanning mode is selected, the control unit actuates thesolenoid 28 so as to move the floor mirror 23-1′ to the first position.When the output of the mode selection switch is off; that is, when themulti-scanning mode is selected, the control unit actuates the solenoidaccordingly so as to move the floor mirror 23-1′ to the first position.

[0385] Owing to the foregoing arrangement, in multi-scanning mode,scanning light is not emitted through the second read window 13 b.However, in single-scanning mode, scanning light is emitted through notonly the second read window 13 b but also the first read window 13 a.When the single-scanning mode is selected, therefore, it is required toinvalidate a bar-code reading operation for a period during whichscanning light is being emitted through the first read window.

[0386]FIG. 53 is a diagram showing the waveforms of signals used for theabove control. In FIG. 53, an output of the mode selection switch isidentical to the one shown in FIG. 41 or 49. A mirror position detectionsignal remains on during a period during which light reflected from areflection surface of the polygon mirror is scanning the floor mirror23-1′, and remains off during any other period during which any otherfloor mirror is being scanned. In this case, the period during which themirror position detection signal remains on may be limited to a periodassociated with any specific reflection surface or may be any of periodsassociated with a plurality of reflection surfaces. In the case shown inFIG. 53, the mirror position detection signal remains on only whilelight reflected from one specific reflection surface of the polygonmirror is scanning the floor mirror 23-1′.

[0387] A light source control signal is sued to control lighting of thelaser light source. When the signal is driven on, the laser light sourceis lit. When it is driven off, the laser light source is put out.

[0388] In the case shown in FIG. 53, when the multi-scanning mode isselected (the output of the mode selection switch is driven off), thelaser light source is lit irrespective of the scan position of lightreflected from the polygon mirror. In contrast, when the single-scanningmode is selected, the light source control signal is driven on for aperiod during which the mirror position detection signal remains on;that is, the floor mirror 23-1′ is being scanned. The laser light sourceis thus lit. For any other period, the light source control signal isdriven off, and thus the laser light source is put out.

[0389]FIG. 54 is a flowchart describing the foregoing control. When adesignated read mode is the single-scanning mode, the control unitdrives the solenoid so as to move the floor mirror 23-1′ to position b(step 922). For only the period during which the floor mirror 23-1′ isbeing scanned, is the laser light source lit (step 923).

[0390] By contrast, when the multi-scanning mode is selected, thecontrol unit drives the solenoid so as to move the floor mirror 23-1′ toposition a (step 924). Thus, the laser light source is lit all the time(step 925).

[0391] As mentioned above, the arrangement shown in FIG. 52 is used togive the control described in FIGS. 53 and 54. In multi-scanning mode,therefore, scanning light is emitted only through the first read window13 a. In single-scanning mode, scanning light is emitted only throughthe second read window 13 b. Only for a period during which scanninglight is being emitted through a read window associated with a readmode, is a reading operation validated. Consequently, incorrectdetection of noise or double reading can be prevented.

[0392] In the case shown in FIG. 52, operation of the light source iscontrolled. In the reader having the arrangement shown in FIG. 52,validation and invalidation of the light detection circuit or ofdecoding may be changed.

[0393]FIG. 55 is a view showing a state in which the reader is placeddirectly on a tabletop (without the use of the stand). In FIG. 55, thereader is laid on the tabletop. As seen from the top view in FIG. 15,the lateral sides of the head of the reader are chamfered obliquely.When the reader is placed on a tabletop, the read window employed facesobliquely up by an angle corresponding to the angulation of the lateralsides of the reader. A bar-code read area is therefore located obliquelyabove the reader.

[0394] When the reader is placed on a tabletop, articles bearing barcodes that are objects of reading pass above the reader. The read windowemployed is therefore directed upward so that a read area will belocated obliquely above the reader. Thus, the read area is set in thevicinity of the positions of passing articles. Thus, the maneuver forbar-code reading can be achieved easily.

[0395] By contrast, if the read window faces substantially horizontally,part of a scan range covered by scanning light would be intercepted bythe tabletop. This poses a problem that the scan range becomessubstantially narrow. Moreover, since bar codes must be passed aposition very close to the tabletop, the maneuverability for readingdeteriorates.

[0396] As mentioned above, when the reader is placed on a tabletopwithout the use of the stand or the like, the read window employed isdirected obliquely upward so that scanning light will be emitted upward.Thus, the maneuverability for reading can be improved.

[0397] When the reader shown in FIG. 55 is used as a hand-held reader,similarly to when the laying stand shown in FIGS. 33A and 33B is used,the grip of the reader can be held readily. Hands need not be changed inorder to grasp the reader. In the case of the reader shown in FIG. 55,especially, since the stand is unnecessary, both the capabilities of astationary reader and hand-held reader can be realized using the onereader.

[0398] When the reader is placed on a tabletop like the reader shown inFIG. 55, the multi-scanning mode is executed in principle. When thereader is placed on a tabletop, one of the lateral sides of the readeris in contact with the tabletop. This nature of the reader is utilizedin order to change read modes automatically.

[0399]FIG. 56 is a view showing a reader having mode detection sensorson the lateral sides thereof. As shown in FIG. 56, the mode detectionsensors are placed one by one on the lateral sides of the 2. The modedetections sensors may be, for example, optical sensors for detecting aquantity of incident light.

[0400]FIG. 57 shows a state in which the reader having the modedetection sensors which is shown in FIG. 56 is placed on a tabletop. Thereader is fundamentally identical to the one shown in FIG. 55 except thepresence of the mode detection sensors. In the case of the reader shownin FIG. 57, the reader is placed on the tabletop so that the right-handside (on the side of the mode detection sensor 17L) of the reader withrespect to the front side of the reader will be the top side.

[0401] In the state shown in FIG. 57, extraneous light enters the modedetection sensor L. The quantity of light incident to the mode detectionsensor 17L does not decrease. By contrast, the mode detection sensor 17R(not shown) is in contact with the tabletop. The quantity of lightincident to the mode detection sensor 17R decreases compared with thatincident to the mode detection sensor L. By utilizing the relationshipbetween the state of the reader and the quantities of light incident tothe mode detection sensors, the read mode is changed into a read modesuitable for the state of the reader on the basis of the quantities oflight incident to the mode detection sensors.

[0402]FIG. 58 is a flowchart describing control of read mode changeusing the mode detection sensors.

[0403] The control unit judges on the basis of the quantities of lightincident to two mode detection sensors if the reader is placed on atabletop (step 931). When it is judged that the reader has been placedon the tabletop (the quantity of light incident to one of the lightdetection sensors decreases), the reader is changed into themulti-scanning mode (step 933). When the quantities of light incident tothe mode detection sensors remain unchanged, the control unit changesthe reader into the single-scanning mode (step 932).

[0404] As mentioned above, read modes are changed automaticallyaccording to whether the reader is placed on a tabletop or it is notplaced thereon (used as a hand-held reader). This obviates the necessityof forming the mode selection switch on the reader.

[0405] When bar-code reading is carried out with the mode selectionswitch held down, there is a possibility that a user may release themode selection switch carelessly. In this case, read modes are changed,through a user does not intend it. In particular, when the switch isreleased in the course of the single-scanning mode that has been set inorder to read a bar code on a bar-code menu, if the single-scanning modeis changed into the multi-scanning mode, there arises a fear that a barcode other than the bar code that is an object of reading may be read.Since the incorrectly-read bar code is proper data, the readerrecognizes that a correct bar code has been read, and reports the resultto the user. When the user remains unaware of the fact that read modeshave been changed, if the user continues processing, incorrectly-inputdata is finalized as input data.

[0406] However, owing to the operation of the mode detections sensors,since read modes are automatically changed according to the placed stateof the reader, it can be prevented that a read mode is changed intoanother read mode that is not intended by a user. Consequently,incorrect input of data can be reduced to the greatest extent.

[0407] When the reader is not placed on a tabletop, a read mode may beeither the multi-scanning mode or single-scanning mode. A read modedesired by a user may be selected. For example, even when the reader isused as a hand-held reader, a suitable read mode is varied depending onwhether the reader is used as a touch reader or a gun reader. When theaforesaid mode selection switch is included in the reader having themode detection sensors, if the reader is used as a hand-held reader,read modes can be changed using the mode selection switch.

[0408]FIG. 59 is a flowchart describing an example of control of readmode change to be employed in the foregoing situation. When the controlunit detects that the quantities of light incident to the mode detectionsensors remain unchanged, it sets the read mode to the single-scanningmode for hand-held reading (step 942). Thereafter, the control unitmonitors if the mode selection switch has been manipulated (step 944).When the mode selection switch is not manipulated, the single-scanningmode is retained (step 946). By contrast, when a user intends to use thereader as a gun reader, if it is detected that the mode selection switchhas been manipulated, the control unit changes the read mode into themulti-scanning mode (step 945). Bar-code reading is then executed.

[0409]FIG. 60 shows a variant of the reader shown in FIG. 56. The readershown in FIG. 60 has detection switches, which may be microswitches, inplace of the optical mode detection sensors. When the reader shown inFIG. 60 is placed on a tabletop as shown in FIG. 57, the detectionswitch on the side of the reader in contact with the tabletop is pressedby the tabletop.

[0410]FIG. 61 is a flowchart describing control of read mode selectionto be performed in the reader shown in FIG. 60.

[0411] The control unit monitors if the mode detection switches havebeen depressed (step 951). When it is judged that either of thedetection switches has been depressed and that the reader has bee placedon a tabletop, the read mode is changed into the multi-scanning mode(step 953).

[0412] when it has not been detected that either of the detectionswitches has been detected, the read mode may be set to a read modedesired by a user (for example, the multi-scanning mode is retained) inthe same manner as that in the reader shown in FIG. 51). When themulti-scanning mode is retained, it can be changed into thesingle-scanning mode by, for example manipulating the mode selectionswitch.

[0413] Alternatively, a microswitch may be formed by the second readwindow 13 b as described below. When the second read window 13 b isbrought into contact with a menu sheet or the like, the microswitch isturned on in order to select the single-scanning mode.

[0414]FIG. 62 is a view for explaining a mechanism for changing the readmode into the multi-scanning mode when the reader is erected on thestand. FIG. 63 is a flowchart describing control of read mode selectionto be performed in the reader shown in FIG. 62.

[0415] A detector (setting sensor) 121 that is a microswitch is placedon the base of the reader. A detection jut is formed on the base of theholder section of the stand. The position of the detection justcoincides with the position of the detector inside the reader when thereader is mounted on the stand.

[0416] When the reader is mounted on the stand, the detector in thereader is pressed by the detection jut. The control unit of the readermonitors the state of the detector 121 (step 951). When detecting thatthe detector has been pressed, the control unit judges that the readerhas been mounted on the stand and changes the read mode into themulti-scanning mode (step 952).

[0417] When the detector has not been pressed, it is thought that thereader is used as a hand-held reader. In this case, the read mode may beset to the single-scanning mode or multi-scanning mode. Whichever of themodes is selected depends on in what form a user uses the hand-heldreader. A read mode is set accordingly.

[0418] In case the reader is used as a gun reader frequently, althoughthe reader is used as a hand-held reader, the read mode should be set tothe multi-scanning mode. Changing into the single-scanning mode shouldbe performed with the manipulation of the mode selection switch.

[0419] On the contrary, in case the reader is used as a touch readermore frequently, since the reader is used as a hand-held reader, theread mode should be set to the single-scanning mode. For using thereader as a gun reader, the mode selection switch is manipulated. Inthis case, unlike the aforesaid system design in which the read mode ischanged into the single-scanning mode with the manipulation of the modeselection switch, the control unit changes the read mode from thesingle-scanning mode to the multi-scanning mode. When the mode selectionswitch is manipulated, the control unit changes the read mode into themulti-scanning mode. When the mode selection switch is not manipulated(the reader is used as a hand-held reader), the single-scanning mode isset.

[0420] In a state in which the reader is set to the single-scanningmode, for reading a bar code on a menu sheet or the like, all bar codeslocated close to the second read window 13 b are read. This poses aproblem that when the second read window 13 b approaches an intended barcode, another bar code located close by may be read. For preventingoccurrence of such a problem, as shown in FIG. 62, microswitches (windowswitches) 181R and 181L are arranged by both edges of the second readwindow 13 b so that when the second read window 13 b is used to read abar code on a menu sheet or the like, the switches 181R and 181L will beturned on.

[0421]FIG. 64 is a flowchart describing control of read mode selectionto be performed when the foregoing window switches are arranged.

[0422] If it is judged at step 961 that the single-scanning mode hasbeen designated, the laser diode is turned off (step 962). It is thenjudged if the window switches 181L and 181R are on (step 963). If theswitches are on, the laser diode is turned on only when the laser beamscans the floor mirror 23-8 (step 964). A bar code is then read (step965).

[0423]FIGS. 65A and 65B are views for explaining an arrangement forchanging read modes when the reader is laid on the laying stand. FIG. 66is a flowchart for describing read mode selection control to be given inthe reader shown in FIGS. 65A and 65B.

[0424] In FIGS. 65A and 65B, an optical mark such as a bar code forinstructing read mode change is formed on the inner surface of a wall642 of all the walls of a laying stand 64 which is opposed to the secondread window.

[0425] When the reader is used as a hand-held reader, if it ispresumably used as a touch reader, it is set to the single-scanningmode. In this state, the operation of the reader is substantiallyinvalidated for a period during which scanning light is emitted throughthe first read window. Bar-code reader is enabled only for a periodduring which scanning light is emitted through the second read window.

[0426] In this state, when the reader is mounted on the laying stand,scanning light emitted through the second read window 13 b scans a barcode 645 formed inside the stand. Thus, the bar code for instructingread mode change is read.

[0427] The control unit of the reader monitors if the bar code has beendetected by light emitted through the second read window. Whenidentifying the read bar code, the control unit judges that the read barcode instructs read mode change (step 962). The control unit thenchanges the read mode from the single-scanning mode to themulti-scanning mode (step 964). Control is thus given so that bar-codereading will be valid even during the period during which scanning lightis emitted through the first read window 13 a.

[0428] When the bar code on the laying stand is not detected, thecontrol unit retains the single-scanning mode as the read mode (step963). Even after the read mode is changed into the multi-scanning mode,bar-code reading using scanning light emitted through the second readwindow is still valid. In the state in which the reader is mounted onthe laying stand, scanning light emitted through the second read windowcontinues scanning the bar code for instructing read mode change whichis formed inside the stand.

[0429] When the reader is dismounted from the laying stand, the bar codefor instructing read mode change which is formed inside the stand is nolonger detected. Based on this fact, the control unit changes the readmode from the multi-scanning mode to the single-scanning mode.

[0430] Thus, read modes can be changed automatically according towhether the reader is mounted on or dismounted from the laying stand.For changing the read mode into the multi-scanning mode despite the useof the reader as a hand-held reader, for example, the mode selectionswitch is manipulated.

[0431]FIG. 67 is a view for explaining another mechanism for modechange. In FIG. 67, a grip sensor 122 is formed on the back side of thegrip. When a user holds the grip 12, the fact is detected by the gripsensor 122. The result of the detection is reported to the control unit.For example, an electrostatic sensor is used as the grip sensor 122.When a person holds the grip, since the electrostatic capacity of thegrip sensor varies, read modes are changed. Even when the grip sensor122 comes into contact with the holder section of the stand, since theelectrostatic capacity of the grip sensor does not vary, read modes arenot changed.

[0432]FIG. 68 is a flowchart describing read mode selection control tobe given in the reader shown in FIG. 67.

[0433] When it is detected owing to the grip sensor 122 that the grip 12has been held (step 966), the control unit changes read modes. In thiscase, the reader is thought to be used as a hand-held reader. Thecontrol unit therefore changes the read mode into the single-scanningmode on the basis of the result of the detection (step 967).

[0434] The position of the grip sensor 122 is not limited to the backside of the grip. However, since it is the back side of the grip whereholding can be checked most reliably, it is most effective to form thegrip sensor at the position.

[0435] Most preferably, the aforesaid switches or sensors used to changeread modes should be formed at positions not interfering with mountingof the reader on the stand. As for the switches or sensors directlymanipulated by a user, they should be formed at positions ensuring easymanipulation for the user.

[0436] When the reader is used as a touch reader, it is important forreliable reading to bring a bar code to scanning light emitted throughthe second read window 13 b. FIG. 69 is a view showing an example of areader capable of notifying a user of a position scanned by a scanningray.

[0437] As already described, in a conventional touch reader, an LED isused to illuminate a bar-code surface entirely. The necessity ofpositioning a read window strictly is therefore low. However, in thecase of the reader of this embodiment, even when the reader is used as atouch reader, a bar code is scanned with a scanning ray such as laserlight. Unless the bar code is located at a position passed by thescanning light, the bar code cannot be read. The read window employedmust therefore be positioned strictly.

[0438] The cover 14 is, as already described, attached to the perimeterof the second read window 13 b of the reader. Scan direction indicatormarks 141 indicating the start and end points of a unidirectionalscanning pattern are inscribed on the right hand and left hand of thecover. This assists a user in checking which position is scanned byscanning light 10 b emitted through the second read window. The scanningray travels along a line linking the apices of the triangular marks.

[0439] The touch reader has the read window thereof approached to a barcode for reading. In the case of the reader shown in FIG. 69, inparticular, the perimeter of the second read window is shielded with thecover 14. It is hard to directly discern a bar code that is an object ofreading. It is also hard to discern which position of the bar code isscanned by scanning light emitted through the second read window 13 b.

[0440] However, since the marks 141 shown in FIG. 69 are inscribed onthe cover 141. The scan position of a scanning ray emitted at leastthrough the second read window 13 b can be judged on the basis of themarks. It can therefore be checked indirectly which part of the bar codeis being scanned. Consequently, the bar code to be read can be readreliably.

[0441]FIG. 70 is a view showing a variant of the reader shown in FIG.69. In FIG. 70, LED indicators 142 are formed at the positions of thescan direction indicator marks 141 shown in FIG. 69. Compared with thecase in which the marks are inscribed, when the LED indicators 142 areformed, a user can discern the marks more easily and check the scanposition of scanning light more easily. The reader shown in FIG. 70 willprove effective when a place in which the reader is used is dark.

[0442] For reading a bar-code menu, when the menu sheet is placed on atabletop, the reader approaches a bar code from immediately above thebar code. If the LED indicators were formed on the back side of thereader, the LED indicators would be identified readily. However, whenthe menu sheet is held by one hand and the reader is held by the otherhand, the lateral side of the reader faces a user's face. If the LEDindicators were formed on the back side of the reader, the user wouldfind it hard to identify them. Even in this situation, as shown in FIG.70, since the LED indicators are formed on the lateral sides of thereader, the LED indicators can be discerned readily.

[0443] When the indication color of the LED indicators may be varieddepending on whether the reader is rested or used to read a bar code,the capability of a read check indicator can be added to the LEDs shownin FIG. 70. This enables a user to check reading and a scan position ofscanning light simultaneously.

[0444]FIG. 71 is a view showing an example of another mechanism forenabling a user to recognize a scan position of scanning light emittedthrough the second read window 13 b. In the case shown in FIG. 71,projections 143 indicating a position and direction to and in whichscanning light is emitted are formed on both edges of the second readwindow. The projection direction of the projections 143 agrees with adirection in which scanning light is emitted.

[0445] The two projections 143 are brought into contact with both edgesof a bar code that is an object of reading, whereby scanning lightemitted through the second read window 13 b can accurately scan the barcode that is an object of reading. The use of such projections obviatesthe necessity of bringing a bar code close to the read window employed.It can therefore be prevented that the bar code is hidden behind theread window. When a bar code is hidden behind the rear window, it cannotbe checked directly which position of the bar code is scanned by thescanning light. This problem will not occur in the reader shown in FIG.71. The state of a bar code being scanned can be discerned directly.

[0446] In the case of the reader shown in FIG. 71, a bar code that is anobject of reading through the second read window 13 b is located at thetips of the projections 143. Preferably, the focal position of scanninglight emitted through the second read window 13 b should therefore bepresent in the vicinity of the tips of the projections.

[0447]FIG. 72 is a view sowing yet another example of a mechanism forenabling a user to identify a scan position of scanning light emittedthrough the second read window 13 b.

[0448] In the reader shown in FIG. 72, crest juts 144 are formed at bothedges of the cover formed on the perimeter of the second rear window.The crest juts 144 have the same significance as the marks shown in FIG.69. Both edges of a bar code that is an object of reading are alignedwith the positions of the crest juts, whereby scanning light emittedthrough the second read window 13 b can scan the bar code reliably. Evenin the case shown in FIG. 72, it can be prevented that a bar code thatis an object of reading is hidden behind the read window.

[0449]FIG. 73 is a view for explaining a mechanism for preventing a barcode that is an object of reading from being hidden behind the readwindow employed. In the reader shown in FIG. 73, a position at which theread window 13 b is formed is lowered by one step from the positionshown in FIG. 70. A transparent cover 145 for properly retaining thespacing between the read window and a bar code is attached to the faceof the read window 13 b.

[0450] Since the read window is located at a one-step lowered position,even when the reader approaches a bar-code surface, the bar code can bediscerned from the back side of the reader. Since a bar code can bediscerned directly, it can be checked directly and easily which positionof the bar code is being scanned. Moreover, for reading a bar code, thebar code is brought into contact with the face of the transparent cover.Since the transparent cover 145 is attached, the spacing between a barcode and the read window can be retained properly. Consequently, it canbe prevented that discerning a bar code and checking a scan positionfrom the back side of the reader are crippled because the reader hasapproached too closely to the bar code.

[0451] When the transparent cover 145 is designed to be detachable andreplaceable, if the face of the transparent cover is flawed because itis brought into contact with a bar code, the transparent cover can bereplaced with a new one. Thus, the influence of the flaw can benullified.

[0452]FIG. 74 is a view showing reading of a bar-code menu. As shown inFIG. 74, the crest juts 144 are formed on the cover on the perimeter ofa read window. A proper space is interposed between a bar code and theread window (crest juts). This makes it easy to discern the bar code anda scan position.

[0453] Moreover, the back side 111 of the reader is streamlined. If theback side of the reader were angular, the angular part would interferewith discernment of a bar code or scan position. However, as shown inFIG. 74, since the back side 111 of the reader is streamlined, even whenthe reader is used for hand-held reading, nothing interferes withdiscernment of a bar code or scan position. A position check can beachieved readily.

[0454]FIG. 75 is a view showing a variant of the reader shown in FIG.74. The back side of the reader shown in FIG. 75 has a concave part 113formed. The formation of the concave part 113 makes it easy to check abar code or scan position from the back side of the reader.

[0455]FIGS. 76A and 76B are views for explaining checking of a bar-codeposition or scan position to be performed in order to read a bar-codemenu 4. The back side 111 of the reader shown in FIGS. 76A and 76B has aslope. The slope is set to have substantially the same angle as theangle of emission of scanning light emitted through the second readwindow 13 b. Since both edges of the cover 14 of the second read window13 b are formed as the juts 114, an operator's line of vision will notbe intercepted by the second read window of the reader. Consequently,the bar-code position or scan position can be checked readily by theoperator.

[0456] Scanning light emitted through the second read window 13 btravels along a line linking the positions of scan position indicatormarks 141 inscribed on the lateral sides of the cover 14. When a barcode is positioned to lie between extensions of the scan positionindicator marks 141, the bar code can be scanned reliably.

[0457] As apparent from FIG. 76A, a tip 114 of the reader is formedlinearly so that the reader can readily be aligned with the orientationof a bar code. The orientation of the tip 114 of the reader agrees withthe scan direction of a scanning ray emitted through the second readwindow 13 b. When the orientation of a bar code is aligned with thelinear tip, the bar code can be scanned thoroughly. This leads to morereliable reading.

[0458] In FIG. 76B, a scan range permitted by multi-directional scanninglight emitted through the first read window 13 a is illustrated forreference. It is seen that the multi-directional scanning light scans awider range than the scanning light 10 b emitted through the second readwindow 13 b.

[0459] Now, a description will be made of the reason why the scanninglight 10 b emitted through the second read window 13 b of the readershown in FIGS. 76A and 76B is not irradiated vertically to a readsurface.

[0460]FIG. 77A is a diagram showing a state in which scanning light isirradiated vertically to a bar code. Scanning light falls on the barcode vertically. The scanning light is therefore reflected from thebar-code surface substantially in its entirety. The quantity of lightreflected from the bar code and received by the reader is therefore verylarge. When the reader is used as a touch reader, the distance of theread window employed from a bar code is so short that the quantity ofscanning light irradiated to the bar code is great. When scanning lightis irradiated vertically to a bar code in this read form, such a problemmay occur that it becomes hard to detect the contrast of the bar codebecause of the too large quantity of reflected light and the bar codecannot therefore be read.

[0461] In the conventional touch reader in which an LED is used toilluminate a bar code, the quantity of light used to illuminate a barcode is not so large as to pose the foregoing problem. In the reader ofthis embodiment, however, since laser light is used to scan a bar code,the quantity of light reflected from the bar code is much larger thanthat in the touch reader using an LED.

[0462] In the reader shown in FIGS. 76A and 76B, it is designed that theemission direction of scanning light emitted through the second readwindow 13 b is not vertical to a bar-code surface. When scanning lightis emitted in such an angle, as shown in FIG. 77B, the scanning light isreflected irregularly from the bar-code surface. The quantity ofreflected light received by the reader is smaller than the quantity ofreflected light of scanning light that is irradiated vertically. Sincethe distance of a bar code from the reader is very small, this reductionin quantity of reflected light does not adversely affect bar-codereading at all.

[0463] As mentioned above, since scanning light emitted through thesecond read window 13 b and used to read a closely-located bar code isirradiated in the direction shown in FIGS. 76A and 76B, it can beprevented that the quantity of light reflected from the bar code becomestoo large. Moreover, the quantity of reflected light can be optimizedfor detection of a bar code.

[0464]FIG. 78 is a side sectional view of the reader of this embodiment.

[0465] A printed-circuit board 120 including a control unit forcontrolling the reader is incorporated in the reader. Theprinted-circuit board extends from the head to the rear end of the grip.An interface cable 3 to be coupled with an external unit is joined withone end of the printed-circuit board.

[0466] A laser light source 21, a condenser 26, a polygon mirror 22,multi-beam stationary mirrors 23-1 to 23-7, a single-beam stationarymirror 23-8, and a condensing sensor 25 are incorporated in the head ofthe reader. The multi-beam stationary mirrors 23-1 to 23-7 correspond tothe floor mirrors 23-1 to 23-7 in FIG. 7, and the single-beam stationarymirror 23-8 corresponds to the floor mirror 23-8 in FIG. 7. The othercomponent elements correspond to those shown in FIG. 7.

[0467] The stationary mirrors are locked in an optical frame 122. Theoptical frame is attached to a cover 121 of the reader via cushioningmembers 124 and 125. Since the reader of the embodiment may be used as ahand-held reader, there is a fear that the reader may suffer a shockwhen it is used to read a bar code or mounted or dismounted on or fromthe stand. When shocks are conveyed to an optical system in the reader,there arises a fear that the optical system may be displaced or damaged.In the reader shown in FIG. 71, the optical frame 122 in which theoptical system is locked is attached to the cover of the reader via thecushioning members 124 and 125 so that shocks applied to the reader willnot be conveyed to the optical system.

[0468] A motor 221 for driving the polygon mirror 22 is especiallysusceptible to shocks. When the motor receives shocks, a bearing may bedamaged. Consequently, a sound may occur during the rotation of themotor. At worst, there is a possibility that the motor may fail. Thepolygon mirror is therefore attached to the optical frame 122 via amotor cushion 126. Owing to the operation of the motor cushion 126, inaddition to the effect of shock reduction by the cushioning members,shocks applied to the motor can be greatly attenuated.

[0469] The condensing sensor 25, laser light source 21, and condensermirror 26 are also locked in the optical frame 122, though FIG. 78 doesnot show them clearly. The optical frame is attached to the reader bodyvia the cushioning members 124 and 125. These cushioning members areused to prevent vibrations stemming from the usage of the reader as ahand-held reader from being conveyed to the optical system.

[0470]FIG. 79 is a view showing the optical frame 122 and partsconstituting the optical system to be locked in the optical frame. FIGS.80 to 83 are views showing a state in which the optical parts are lockedin the optical frame 122.

[0471] The optical frame 122 is molded as a united body using, forexample, a resin. The eight floor mirrors 23-1 to 23-8, condenser mirror26, laser light source 21, light reception sensor 25, polygon mirror 22(polygon motor), and cushioning members and motor cushions 124, 125, and126 are locked in the optical frame 122.

[0472] The reflection surfaces of the polygon mirror 22 are affixed torespective sides of a base whose cross section is shaped like atrapezoid. Alternatively, the polygon mirror may be molded as a unitedbody using a resin, and reflection membranes may be deposited on thereflection surfaces.

[0473] The base of the polygon mirror is engaged with an axis ofrotation of the motor 221 placed on a substrate. Leads over whichsignals or the like used to drive the motor are fed are coupled with oneend of the substrate. The polygon motor 221 is locked in the opticalframe 122 via the motor cushion 126. The polygon motor 221 is screwed tothe optical frame 122 through a screw hole bored in the substrate 120.

[0474] The light reception sensor 25 is placed on a substrate. A controlunit for controlling the light reception sensor is mounted on thesubstrate 120. A screw hole bored in the substrate on which the lightreception sensor 25 is placed is located at a position coincident with ascrew hole bored in the optical frame 122. The substrate on which thelight reception sensor 25 is placed is screwed to the optical frame 122.

[0475] The laser diode (laser light source) 21 is secured to anattachment member with two screws. The attachment member having thelaser diode 21 is screwed to an attachment plate formed on the lateralside of the optical frame 122, whereby the laser diode is secured to theoptical frame. The emission direction of laser light emanating from thelaser diode 21 is a direction toward a small reflection mirror 26′attached to the center of the condenser mirror 26.

[0476] Planes on which the floor mirrors 26-1 to 26-8 are affixed isplaced on the base of the optical frame 122. The numerals written on thebase correspond to the reference numerals denoting the floor mirrors.The floor mirrors are affixed to the positions.

[0477] The condenser mirror 26 has both edges thereof supported by theoptical frame 122. Both the edges have three stems which are fitted intoholes bored in a first clamp and second clamp. The condenser mirrorattached to the clamps is locked in the optical frame.

[0478]FIG. 84 is a view showing the condenser mirror in enlarged form.The stems 263 and 264 are formed on the left-hand and right-hand sidesof the condenser mirror 26 and located coaxially. The stems 263 and 264serve as an axis of rotation of the condenser mirror 26. The stem 265 islocated under the stem 264 on the side of the condenser mirror havingthe stem 264.

[0479]FIG. 85 is a view showing the condenser mirror 26 attached to thefirst and second clamps 261 and 262, and a portion of the optical frame122 in which the condenser 26 is locked. A slit (first hole) 266extending horizontally is formed in a first wall of the optical frame122. A second hold 267 and a third hole 268 shaped like an arc with thesecond hole as a center are formed in a second wall of the opticalframe.

[0480] The first stem 263 of the condenser mirror 26 is fitted into thefirst hole 266. The second and third stems 264 and 265 of the condensermirror are fitted into the second and third holes 267 and 268 of theoptical frame.

[0481] The first hole 266 of the optical frame 122 is an elongated holeextending horizontally. The side of the condenser mirror 26 having thefirst stem 263 can therefore be moved back and forth with the condensermirror locked in the optical frame 122. Moreover, the second stem 264 ofthe condenser mirror 26 is merely fitted into the second hole 267.However, the third hole 268 of the optical frame is shaped like an arcwith the second hole 267 as a center. The other side of the condensermirror 26 having the second and third stems 264 and 265 can therefor bepivoted back and forth with the second stem 264 as a fulcrum.

[0482] Owing to the foregoing structure, the condenser mirror can bemoved back and forth by moving the side of the condenser mirror 26having the first stem 263. The sideways position of the condenser mirrorcan thus be adjusted. Moreover, the reflection surface of the condensermirror 26 can be tilted vertically by pivoting the other side of thecondenser mirror 26 having the second and third stems 264 and 265. Thevertical inclination of the condenser mirror can thus be adjusted.

[0483] The condenser mirror 26 incorporated in the conventional readeris fixed to a member (metallic plate) having elasticity. The angle ofthe condenser mirror is adjusted by tightening and adjustment screwinserted into the back side of the frame. This structure cannot preservea space between the condenser mirror 26 and frame.

[0484] By contrast, in the reader of this embodiment, scanning lightreflected from the floor mirror 23-8 must be directed toward the secondread window 13 b. It is therefore required to preserve a space, throughwhich scanning light passes, behind the condenser 26. However, accordingto the conventional method of attaching the condenser mirror, asufficient space through which scanning light can pass cannot bepreserved behind the condenser mirror 26.

[0485] In the case of the condenser mirror 26 shown in FIG. 84, both theedges of the condenser mirror 26 are attached to the optical frame 122.A sufficient space can therefore be preserved behind the optical frame.Furthermore, alignment of the condenser mirror 26 is achieved by movingboth the edges of the condenser mirror. A mechanism for securing thecondenser mirror can be used in common as a mechanism for aligning thecondenser mirror. Consequently, the number of parts can be reduced andthe space around the condenser mirror can be saved.

[0486] Incidentally, the first and second clamps 261 and 262 each havean elongated hole. The aligned condenser mirror can be secured byscrewing the first and second clamps to the optical frame 122 throughscrew holes bored in the optical frame.

[0487]FIG. 80 shows the optical frame 122 in a state in which all theparts are locked in the optical frame. The floor mirror 23-8 is hiddenbehind the condenser mirror 26. Likewise, the polygon mirror is hiddenunder the substrate on which the light reception sensor 25 is mounted.All the optical parts are thus locked in the optical frame,, whereby theoptical system can be constructed as a united body. Furthermore, theeffect of the cushioning members of absorbing shocks that may beconveyed to the optical system can be intensified.

[0488] FIGS. 81 to 83 are, similarly to FIG. 80, views showing theoptical frame accommodating the optical parts in three directions. InFIGS. 81 to 83, the polygon mirror, light reception sensor, and the likeare omitted. In particular, as apparent from the top view, a sufficientspace that is wide enough for scanning light emanating from the floormirror 23-8 and light reflected from a bar code and incident to thefloor mirror 23-8 to pass is preserved between the back margin of theoptical frame 122 and the condenser mirror 26.

[0489] One cushioning member 130 having a circular cross section isattached to each of the right-hand and left-hand sides of the opticalframe 122. The cushioning members are each formed by joining large roundmembers with a small round member inserted into the centers thereof.Slits formed in the cover of the reader body are engaged with the gapsbetween the large round members. Thus, the optical frame is not directlyattached to the cover. Shocks applied to the reader are thereforeabsorbed by the cushioning members. Cushioning members are affixed ontothe border of the optical frame, though they are not shown in FIGS. 81to 83. These cushioning members are interposed between the contactsurfaces of the optical frame and reader body, and absorb shocks.

[0490] The head of the reader further comprises a multi-beam exit (firstread window) 13 a and a single-beam exit (second read window) 13 b. Thesingle-beam exit is angled so that the emission direction of scanninglight emitted through the second read window 13 b will not be a verticaldirection. The angle at which the single-beam stationary mirror 23-8 ismounted is also defined so that scanning light will be emitted in thedirection. As shown in FIG. 78, the tip of the cover is shaped so thatwhen the cover is hit against a bar-code surface, scanning light emittedthrough the second read window 13 b will not be irradiated vertically tothe bar code.

[0491] A printed-circuit board having a control unit for controlling theoperations of the whole reader is located behind (on the right-hand sideof) the optical system incorporated in the reader. An interface cable 3to be coupled with an external unit is attached to one end of theprinted-circuit board.

[0492] A switch 127 and switch 128 are located on teh back side of thereader. The switch 128 corresponds to the aforesaid mode selectionswitch 15 b and has a switch plate. The switch 127 corresponds to theswitch 15 c shown in FIG. 15 and is used to change the other functions.

[0493] The reader shown in FIG. 78 is, as already described, mounted onthe stand and used as a stationary reader. In particular, when thereader is erected on the stand, if the center of gravity of the readeris located in an upper part of the 2, the holder section to which thereader is fitted tends to pivot because of the weight of the reader. Theorientation of the read window employed of the window mounted on thestand becomes inconstant.

[0494] The reader of this embodiment therefore has the center of gravityset as low as possible. In particular, preferably, the center of gravityshould be present in the grip.

[0495] For setting the center of gravity as low as possible in theillustrated state, in the reader of this embodiment, the polygon mirroris placed below the stationary mirrors. What is the heaviest among allthe components of the reader is the motor 221 for driving the polygonmirror. The center of gravity can be lowered by placing the motor as lowas possible.

[0496] However, the grip needs a certain length. The motor 221 fordriving the polygon mirror 22 cannot be stowed in any place other thanthe head. Even when the polygon mirror and motor are arranged in a lowerarea of the head, the center of gravity cannot be shiftedsatisfactorily. In the reader shown in FIG. 78, therefore, a weight 123used to lower the center of gravity is stowed in the grip. Since thereis a sufficient space in the grip, the center of the gravity of thereader can be lowered as much as possible by setting the weight in thespace. Even when the reader is mounted on the stand, the orientation ofthe read window employed can be kept constant.

[0497] If the center of gravity were located at an upper area, when thegrip is held, the head would feel heavier than it actually is. However,since the center of gravity of the reader is shifted to the grip to thegreatest extent, when a user holds the grip of the reader, he/she willnot feel the head heavy but can grasp the reader in a stable manner.

[0498]FIG. 86 is a view showing an example of a reader in which thescanning pattern supplied through the second read window 13 b has beenmodified. In the reader shown in FIG. 86, a plurality of scanning rays(two rays in FIG. 86) of which scan directions are mutually parallel andof which angles of emission are slightly different from each other areemitted through the second read window 13 b. Thus, the scanning patternsupplied from the second read window 13 b is composed of a plurality ofscanning rays. Even if a bar code to be brought to the face of the readwindow is slightly deviated from the position of the read window, thebar code can be scanned by either of the scanning rays. Alignment of abar code need not be worried about very much.

[0499] For generating a plurality of scanning rays, scanning raysreflected from a plurality of reflection surfaces of the polygon mirrorhaving different inclinations must fall on the single-beam stationarymirror. Since the inclinations of the reflection surfaces of the polygonmirror are different from one another, the angles of incidence ofscanning rays incident to the single-beam stationary mirror becomedifferent from each other. The different angles of incidence result indifferent emission directions of the scanning rays.

[0500] For example, in the case shown in FIGS. 8 and 9, a scanning rayincident to the floor mirror 23-8 (corresponding to the single-beamstationary mirror) is reflected only from the fourth reflection surfaceof the polygon mirror. The number of scanning rays emitted through thesecond read window 13 b is therefore one. However, when scanning raysare reflected from the other reflection surfaces are allowed to fall onthe floor mirror 23-8, the number of scanning rays emitted through thesecond read window 13 b increases accordingly.

[0501]FIG. 87 shows a variant of the reader shown in FIG. 86, wherein ascanning ray emitted through the second read window is scanned in rasterform. FIG. 88 is a side sectional view of a reader for realizing theraster-form scanning shown in FIG. 89. A structure shown in FIG. 88 isbasically identical to that shown in FIG. 78. FIG. 89 is a flowchartdescribing control to be given in order to select raster-form scanning.

[0502] In the reader shown in FIG. 88, a mirror driving actuator 129 islocated below the single-beam mirror 23-8. The operation of the mirrordriving actuator 129 is controlled by a control unit that is not shown.When the mirror driving actuator 129 is driven, the single-beam mirror23-8 is moved back and forth. The scan timing of scanning lightreflected from the polygon mirror 22 and the drive timing of the mirrordriving actuator 129 are adjusted so that the scanning light emittedfrom the second read window 13 b will trace a raster-form trajectory asshown in FIG. 87.

[0503] To be more specific, when the read mode is the single-scanningmode, the control unit drives the window driving actuator 129 (step971). The drive timing comes after the scan by one scanning ray iscompleted and before the next scan is started. The magnitude of a driveis varied depending on a pitch of a parallel-line pattern.

[0504] The reader shown in FIG. 87 can exert the same effect as thereader shown in FIG. 86. Moreover, when a so-called two-dimensional barcode must be read using scanning light emitted through the second readwindow, it is required to scan the two-dimensional bar code horizontallyand vertically. For reading such a two-dimensional bar code, as shown inFIG. 87, scanning the scanning light emitted through the second readwindow 13 b in raster form is very effective.

[0505] As already described, preferably, the focal position of scanninglight should be set in the vicinity of the position of a bar code to beread. For reading a bar code through the second read window 13 b, sincethe bar code is located very close to the read window, the focalposition of scanning light is set in the vicinity of the second readwindow 13 b. Incidentally, scanning light emitted through the first readwindow 13 a is set at a position away from the read window because ofits associated read form.

[0506] Scanning light 10 a emitted through the first read window 13 aand scanning light 10 d emitted through the second read window 13 b areproduced by the same optical system. It is therefore very hard todifferentiate one focal position from the other. The differentiation canbe achieved to some extent by differentiating the lengths of light pathsof the scanning light in the reader. Thinking of the recent demands fora more compact reader, the lengths of the light paths cannot beincreased.

[0507] Moreover, it is also required to vary the read depths (distancesin a back-and-forth direction permitting bar-code reading) of scanninglight emitted through the first and second read windows.

[0508] For reading a bar code through the first read window 13 a, thereis a necessity of widening a read range three-dimensionally. It istherefore required to increase the read depth of scanning light emittedthrough the first read window 13 a.

[0509] By contrast, for reading a bar-code menu 4 through the secondread window 13 b, anything other than a bar code that is an object ofreading must not be read. However, when the read depth of scanning lightemitted through the second read window 13 b is large, while the readeris moving over the menu sheet 4, any bar code (that is not the bar codeto be read) recorded on the menu sheet 4 may be read. The read depth ofscanning light emitted through the second read window 13 b must besmall.

[0510] For decreasing the read depth of scanning light, the scanninglight to be emitted is spread, or on the contrary, focused. In contrast,to make the focal position of scanning light close to a read window, thescanning light to be emitted must be focused.

[0511] In the reader shown in FIG. 90, a beam reshaping lens 130 isplaced in the vicinity of the second read window 13 b. The beamreshaping lens 130 is a convex cylindrical lens, focuses scanning lightin a vertical direction in FIG. 90, but does not change the diameter ofthe light in a horizontal direction (corresponding to a scan direction).Using this kind of beam reshaping lens, the focal position of thescanning light can approach the second read window. Furthermore, theread depth of the scanning light can be decreased.

[0512] Now, the reason why a cylindrical lens is used as the beamreshaping lens 130 will be described.

[0513] Especially, when the diameter of light in a vertical direction issmaller than that in a scan direction, if a printed bar code has amissing portion as shown in FIG. 91A, the thickness of a bar of the readbar code may be recognized incorrectly. That is to say, in the case ofFIG. 91A, although a bar 1 originally has a thickness a, when a missingportion thereof is scanned, the reader may recognize that the bar 1 hasa thickness b. Bar-code reading is achieved incorrectly.

[0514] When the diameter of light in the vertical direction is madelarger than that in the scan direction, a not-missing portion of a barcan be scanned as shown in FIG. 91B. The reader detects a bar code onthe basis of an entire quantity of light emanating from a portionscanned by scanning light. In the case shown in FIG. 91B, although thebar 1 has a missing portion, the reader can recognize that the bar 1 hasthe thickness a.

[0515] As mentioned above, when the diameter of light in the verticaldirection is made larger than that in the scan direction, incorrectreading caused by the missing portion of a bar shown in FIG. 91A can beprevented.

[0516] By contrast, if the diameter of light in the scan direction weremade larger, the bar 1 and a bar 2 would be scanned by scanning lightsimultaneously as shown in FIG. 91C. This poses a problem that thereader cannot distinguish the bar 1 from the bar 2. The diameter oflight in the scan direction must not be made larger.

[0517] For the above reason, a cylindrical lens is used as the beamreshaping lens.

[0518]FIG. 92 is a variant of the reader shown in FIG. 90. In the caseof the reader shown in FIG. 92, a cylindrical concave mirror is used asthe floor mirror 23-8′ in place of the cylindrical convex lens 130. Inthis case, the floor mirror 23-8′ exerts the same operation as thecylindrical convex lens. That is to say, the focal position of scanninglight is close to the second read window and the read depth of thescanning light is decreased.

[0519] When the foregoing cylindrical convex lens 130 and concave mirrorare used in combination, reflected light received from a bar code can bevaried depending on a distance of the bar code.

[0520] For example, when the cylindrical concave mirror 23-8′ is used,light reflected from a bar code is converged on the cylindrical concavemirror 23-8′. The focal position of light reflected from the cylindricalconcave mirror is varied depending on a distance between the cylindricalconcave mirror and bar code. For reading a bar code through the secondread window 13 b, when the bar code is located at an optimal readposition, reflected light to be converged on the cylindrical concavemirror 23-8′ (plus a condenser mirror) must be focused on the face of alight reception sensor.

[0521] Owing to the above arrangement, light reflected from a bar codelocated away from the second read window 13 b does not focus on thelight reception surface of the light reception sensor, but goes out offocus. The light reflected from the bar code located away from thesecond read window cannot therefore be recognized by the reader. Thus,the read depth is substantially decreased.

[0522] A method of varying a quantity of scanning light is conceivableas another method for adjusting a read depth. When the quantity ofscanning light diminishes, a quantity of light reflected from a bar codelocated away from a read window decreases. The reader cannot detect thereflected light. By contrast, when the quantity of scanning light isincreased, a bar code separated by a distance comparable to the increasefrom the read window can be read.

[0523] During a period during which scanning light is being emittedthrough the first read window 13 a, the quantity of scanning light isincreased. Moreover, during a period during which scanning light isbeing emitted through the second read window 13 b, the quantity ofscanning light is decreased. The degree of a change in quantity of lightis set according to a desired read depth. Owing to this system design,the read depth of scanning light emitted through each read window can besubstantially adjusted without the necessity of using an optical partsuch as a lens.

[0524] A method similar to the one illustrated in FIGS. 36 to 39 can beadopted as a method for identifying a read window through which scanninglight is emitted.

[0525] It is important to notify a user of the reader of whether thereader is set to the single-scanning mode or multi-scanning mode. Inparticular, when a bar code is read, if whichever read mode is set toread the bar code is notified, it can be reported to a user that, forexample, a bar code supposed to be read in single-scanning mode has beenread in multi-scanning mode.

[0526] Take for instance a reader in which the read mode can be changedto the single-scanning mode by pressing the mode selection switch. Inthis case, for reading a bar-code menu, the read mode must be changed tothe single-scanning mode. A user moves the reader close to a bar codethat is an object of reading while pressing the mode selection switch.However, in the case of a reader in which when the mode selection switchis released, the read mode is changed to the multi-scanning mode, thereis a possibility that when a user releases the mode selection switchcarelessly, the read mode is changed in the other, though the user didnot intend it.

[0527] In such a case, the possibility that a bar code that is not anobject of reading may be scanned and read using a scanning patternsupplied through the first read window becomes higher. Since all barcodes recorded on a menu sheet are valid, even if a bar code that is nota desired one is read because read modes have been changed, the readerconsiders that bar-code reading has been achieved correctly and reportsthe result of bar-code reading.

[0528] At this time, if it can be reported to the user in which readmode the reader operates or in which read mode the bar code has beenread, it can be notified whether or not the reported bar-code readingmeets the user's intention. Consequently, if necessary, input bar-codedata can be invalidated or a desired bar code may be read.

[0529]FIG. 93 is a functional block diagram of a reader capable ofmaking such notification. A controller 225 controls the operations ofthe whole reader, and is connected to a mode selection switch 224, alaser light source 21, and a light detecting circuit 25. Furthermore, anLED 51 and speaker 19, used to notify a user of a bar-code readingsituation, are connected to the controller 225.

[0530]FIG. 94 is a flowchart describing indication control for the LEDused to notify a user of a read mode in which the reader shown in FIG.93 has been set for reading a bar code.

[0531] The controller 225 first recognizes a designated read mode (step975). When the designated read mode is the single-scanning mode,indication control for the single-scanning mode is selection (step 976).By contrast, when the designated read mode is the multi-scanning mode,the controller selects indication control for the multi-scanning mode(step 977). For example, when a bar code has been read normally, the LEDis lit through the selected indication control (step 987).

[0532] Herein, it is preferable that an indication of thesingle-scanning mode and an indication of the multi-scanning mode beindications mutually-distinguishable at sight.

[0533]FIG. 95 is a flowchart describing control of rumbling of thespeaker, which is used to notify a user of a read mode in which thereader shown in FIG. 93 has been set for reading a bar code.

[0534] The controller first recognizes a designated read mode (step980). When the designated read mode is the single-scanning mode,rumbling control for the single-scanning mode is selected (step 981). Bycontrast, when the designated read mode is the multi-scanning mode, thecontroller selects rumbling control for the multi-scanning mode (step982). For example, when a bar code is read normally (step 983), thespeaker is driven to generate a rumbling sound through the selectedrumbling control (step 984).

[0535] Herein, it is preferable that a rumbling sound for thesingle-scanning mode and a rumbling sound for the multi-scanning mode berumbling sounds mutually-distinguishable at sight.

[0536]FIG. 96 is a flowchart describing control of varying the length ofa rumbling sound between the single-scanning mode and multi-scanningmode in order to distinguish one read mode from the other. Herein, forthe single-scanning mode, the rumbling sound is made longer. For themulti-scanning mode, the rumbling sound is made shorter.

[0537] The controller first recognizes a designated read mode (step986). When the designated read mode is the single-scanning mode, thecontroller sets the rumbling sound to a longer one (step 987). Bycontrast, when the designated read mode is the multi-scanning mode, thecontroller sets the rumbling sound to a shorter one (step 988).

[0538] Thereafter, every time bar-code reading is carried out, thecontroller drives the speaker according to a designated length of therumbling sound and allows the speaker to generate a rumbling sound (step990).

[0539]FIG. 97 is a flowchart describing control for varying the volumeof a rumbling sound according to a designated read mode unlike thecontrol described in FIG. 96. In the case described in FIG. 97, inparticular, the rumbling sound is made larger for the single-scanningmode, and made smaller for the multi-scanning mode.

[0540] The controller first recognizes a designated read mode (step991). When the designated read mode is the single-scanning mode, thecontroller sets the rumbling sound to a larger volume (step 992). Bycontrast, when the designated read mode is the multi-scanning mode, thecontroller sets the rumbling sound to a smaller volume (step 993).

[0541] Thereafter, every time bar-code reading is carried out (step994), the controller drives the speaker according to a designated volumeof the rumbling sound and allows the speaker to generate a rumblingsound (step 995).

[0542]FIG. 98 is a flowchart describing control for varying the numberof rumbling sounds given by the speaker according to a designated readmode.

[0543] The controller recognizes a designated read mode (step 996). Whenthe designated read mode is the single-scanning mode, the number ofrumbling sounds is set to a value specified for the single-scanning mode(for example, one) (step 997).

[0544] By contrast, when the designated read mode is the multi-scanningmode, the controller sets the number of rumbling sounds to a valuespecified for the multi-scanning mode (for example three) (step 998).

[0545] Thereafter, every time a bar-code is read (step 999), thecontroller generates a designated number of rumbling sounds (step 1000).

[0546]FIG. 99 is a flowchart describing control for varying the pitch ofa rumbling sound given by the speaker according to a read mode. In thecase shown in FIG. 99, in particular, the pitch of the rumbling sound ismade higher for the single-scanning mode.

[0547] The controller first recognizes a read mode (step 1010). When thesingle-scanning mode is designated, the controller sets the rumblingsound to a higher pitch (step 1011).

[0548] By contrast, when the designated read mode is the multi-scanningmode, the controller sets the rumbling sound to a lower pitch (step1012).

[0549] Thereafter, every time a bar code is read (step 1013), thecontroller operates the speaker according to a designated pitch of therumbling sound (step 1014).

[0550]FIG. 100 is a flowchart describing control for notifying a user ofa currently-set read mode using an LED indicator. Herein, the LEDflickers in single-scanning mode, and is lit continually inmulti-scanning mode.

[0551] First, when a read mode is selected, the controller recognizesthe read mode (step 1020). When the single-scanning mode is selected,control of flickering the LED is selected and the LED flickers (step1021). By contrast, when the multi-scanning mode is selected, thecontroller selects control of continual lighting and the LED is litcontinually (step 1022).

[0552] LED control is changed from one to the other concurrently withchanging of the read mode from the multi-scanning mode to thesingle-scanning mode or vice versa which has been described inconjunction with FIG. 41. Specifically, when the multi-scanning mode isselected, the controller changes LED control into continual lighting,and gives control for validating the multi-scanning mode; that is,reading to be performed during a period during which scanning light isemitted through the first read window.

[0553] By adopting the foregoing method, a read mode set at that timecan be reported to a user. Incorrect bar-code reading (reading withoutselecting a read mode that should be selected) can therefore beprevented. In particular, when the method of notifying a read modeirrespective of the result of reading is adopted, it can be reported toa user that manipulating the mode selection switch is requested.

[0554] As a method for giving different indications using the LED, asidefrom the method of flickering or continually lighting the LED, there isa method of changing indication colors of the LED.

[0555] Incidentally, for varying a rumbling sound, an interval betweenrumbling sounds may be varied according to a read mode.

[0556] The reader in which the first read window 13 a and second readwindow 13 b are independent windows has been described so far.Alternatively, as shown in FIG. 101, the number of read windows may beone. Herein, a read window is divided into a first area 13 c throughwhich a scanning pattern composed of numerous rays is supplied, andsecond area 13 d through which a scanning ray suitable for reading abar-code menu is emitted. In the case shown in FIG. 101, a mark definingthe second area is inscribed around the area. This mark enables a userto identify a position from which scanning light is emitted. Needless tosay, the mark need not be inscribed on the face of the read window. Aslong as scanning patterns suitable for respective read modes can besupplied, an object of the present invention can be accomplishedsatisfactorily.

[0557] In the embodiment described so far, a scanning pattern issupplied from each of the first read area and second read area.Alternatively, the areas may be united into one, and multi-scanning maybe carried out in principle. For performing single-scanning, a specificscanning ray constituting a multi-scanning pattern is selected, andbar-code reading is validated only during a period during which thescanning ray is emitted. In the case of the scanning pattern shown inFIG. 10, since the scanning ray 23-1 is scanned horizontally, thescanning ray 23-1 alone is used in single-scanning mode.

[0558] In this case, it becomes unnecessary to include the floor mirror23-8 and second read window 13 b in the reader. The scanning pattern23-8 shown in FIG. 10 will not be created. Moreover, the components ofthe optical system are only the floor mirrors 23-1 to 23-5 as shown inFIG. 102. The reader can have an area for forming a read window reducedas shown in FIG. 103. Assuming that the specific scanning ray is ascanning ray reflected from the floor mirror 23-1, in single-scanningmode, bar-code reading is validated only during a period during whichthe floor mirror 23-1 is being scanned (the light source is lit, thelight reception circuit is validated, or decoding is validated).

[0559] Judging whether or not light reflected from the polygon mirror isscanning the floor mirror 23-1 is achieved by utilizing the slits formedin the polygon mirror which are shown in FIG. 36 and thereafter.Moreover, the system design for validating bar-code reading only duringa period during which the floor mirror 23-1 is being scanned is the sameas the one described previously.

[0560] In the description made so far, one read mode is changed to theother only during a period during which the mode selection switch isheld down. When the mode selection switch is released, the one read modeis reset. However, the mode selection switch is not limited to thisstructure. Alternatively, every time the mode selection switch ispressed (it need not be pressed continually), read modes may be changed.

1. An optical reader for scanning a mark carried by an article usingscanning light, detecting light reflected from said mark, and thusreading information represented by said mark, comprising: a lightsource; a scanning means that is driven by a driving means and scanslight emanating from said light source; a plurality of reflectionmirrors for reflecting scanning light scanned by said scanning means andcreating a scanning pattern composed of a plurality of scantrajectories; a read window through which scanning light reflected fromsaid reflection mirrors is emitted; and a light receiving means forreceiving light reflected from said mark, said optical reader furthercomprising: a mode changing means for changing a plurality of operationmodes among which one or ones of said plurality of scan trajectories tobe validated for reading are different; said plurality of operationmodes including a specific scanning ray mode in which reading said markusing only a specific scan trajectory constituting said scanning patternis validated and reading said mark using the other scan trajectories isinvalidated.
 2. An optical reader according to claim 1, wherein: saidread window comprises a first area and a second area; scanning raystracing said other scan trajectories are output through said first area;and a scanning ray tracing said given scan trajectory is output throughsaid second area.
 3. An optical reader according to claim 2, whereinsaid first area is a first read window, and said second area is a secondread window independent of said first read window.
 4. An optical readeraccording to claim 3, wherein: the emission direction of a scanning raytracing said given scan trajectory is obliquely up relative to scanningrays tracing said other scan trajectories; and said second read windowis located above said first read window, and the face of said secondread window is located obliquely to the face of said first read window.5. An optical reader according to claim 1, wherein: said scanning meansis a rotary polygon mirror that has a plurality of reflection surfacesand that is driven to rotate by means of said driving means; and atleast one of said plurality of reflection surfaces is placed at anangle, which is different from an angle at which the other reflectionsurfaces are placed, with respect to an axis of rotation of said rotarypolygon mirror.
 6. An optical reader according to claim 1, wherein saidreflection mirrors include a first group of reflection mirrors fordetermining said other scan trajectories and a second group ofreflection mirrors for determining said given scan trajectory.
 7. Anoptical reader according to claim 6, wherein said second group ofreflection mirrors comprises a single reflection mirror.
 8. An opticalreader according to claim 7, wherein said other scan trajectories aretraced by a plurality of intersecting scanning rays, and said giventrajectory is traced by a scanning ray scanned in one direction.
 9. Anoptical reader according to claim 1, wherein the focal position ofscanning rays tracing said other scan trajectories is set to a positionseparated by a first distance from said first area, and the focalposition of a scanning ray tracing said given scan trajectory is set toa second position that is closer to said read window than said firstposition.
 10. An optical reader according to claim 9, wherein saidsecond position lies on the face of said second area of said readwindow.
 11. An optical reader according to claim 1, wherein a scan widthon said read window permitted by a scanning ray tracing said given scantrajectory is larger than a scan width on said read window permitted byscanning rays tracing said other scan trajectories.
 12. An opticalreader according to claim 1, further comprising emission positionindicating means for indicating positions between which a scanning raytracing said given scan trajectory is emitted through said read window.13. An optical reader according to claim 12, wherein said emissionposition indicating means are marks inscribed on the sides of said readwindow.
 14. An optical reader according to claim 12, wherein saidemission position indicating means are indicating means for indicatingthe start point and end point of scanning light emitted through saidread window and notifying a user of the fact that reading said mark iscompleted.
 15. An optical reader according to claim 12, wherein saidemission position indicating means are projections projecting frompositions coincident with said start point and end point of scanninglight emitted through said read window.
 16. An optical reader accordingto claim 15, wherein said projections are extending to said focalposition of a scanning ray that is emitted through said read window andthat traces said given scan trajectory.
 17. An optical reader accordingto claim 3, wherein said second read window is located at a positionreceding from said first read window.
 18. An optical reader according toclaim 17, further comprising a transparent cover attached to the face ofsaid second read window, wherein said focal position of a scanning raythat is emitted through said second read window and traces said givenscan trajectory lies at the tip of said transparent cover.
 19. Anoptical reader according to claim 1, further comprising a mode selectioninstructing means for instructing which of said plurality of operationmodes should be selected, wherein said mode changing means selects anoperation mode instructed by said mode selection instructing means. 20.An optical reader according to claim 19, wherein said mode selectioninstructing means is a switch to be manipulated by a user.
 21. Anoptical reader according to claim 19, wherein said mode selectioninstructing means is placed on the top of said switch and thatpressurizes said switch.
 22. An optical reader according to claim 19,wherein: said mode selection instructing means comprises a plurality ofmanipulable parts; and the contents of instruction made by saidinstructing means are changed into the contents of instruction otherthan selection of any of said plurality of operation modes according towhether one of said plurality of manipulable parts is manipulated orsaid plurality of manipulable parts are manipulated simultaneously. 23.An optical reader according to claim 19, wherein said mode selectioninstructing means includes a detecting means located on at least one ofthe lateral sides of said optical reader, and any of said plurality ofoperation modes is selected according to a mounted state of said opticalreader which is detected on the basis of an output of said detectingmeans.
 24. An optical reader according to claim 19, wherein: saidoptical reader can be mounted in a specific holding member; said modeselection instructing means is a set detecting means for detectingwhether or not said optical reader is mounted in said specific holdingmember; and when said set detecting means detects that said opticalreader is mounted in said specific holding member, an operation modeother than said specific scanning ray mode is selected.
 25. An opticalreader according to claim 24, wherein said set detecting means is aswitch to be pushed by a jut formed on said specific holding member whensaid optical reader is mounted in said specific holding member.
 26. Anoptical reader according to claim 24, wherein said set detecting meansis a specific mark detecting means that when said optical reader ismounted on said specific holding member, detects if scanning lightemitted through one of said areas of said optical reader has detectedsaid mark.
 27. An optical reader according to claim 19, furthercomprising a second instructing means for use in designating anoperation mode, wherein an operation mode is selected according to acombination of the state of said first instructing means and the stateof said second instructing means.
 28. An optical reader according toclaim 1, wherein said mode changing means gives control so that in saidgiven operation mode, said light source will be lit only for a periodduring which is a scanning ray tracing said given scan of trajectory isbeing output.
 29. An optical reader according to claim 28, wherein saidspecific scan trajectory validating means gives control so that in anymode other than said given operation mode, said light source is put outfor a period during which scanning rays tracing said other scantrajectories are being output.
 30. An optical reader according to claim1, wherein said specific scan trajectory validating means gives controlso that in said given operation mode, the operation of said lightreceiving means will be validated only for a period during which ascanning ray tracing said given scan trajectory is being output.
 31. Anoptical reader according to claim 30, wherein said specific scantrajectory validating means gives control so that in any mode other thansaid specific operation mode, the operation of said light receivingmeans will be invalidated for a period during which scanning raystracing said other scan trajectories are being output.
 32. An opticalreader according to claim 31, wherein invalidating the operation of saidlight receiving means is invalidation of decoding of said read mark. 33.An optical reader according to claim 3, wherein said light source,scanning means, plurality of reflection mirrors, read window, and lightreceiving means are stowed in a head, further comprising a grip thatcommunicates with said head and enables a user to grasp said opticalreader.
 34. An optical reader according to claim 33, wherein the backside of said head is molded obliquely.
 35. An optical reader accordingto claim 33, wherein the back side of said head is molded to be angledin the emission direction of scanning light emitted through said secondarea.
 36. An optical reader according to claim 34, where in the backside of said head has a concave dent formed so that scanning lightemitted through said second area can be discerned.
 37. An optical readeraccording to claim 1 further comprising a notifying means for notifyinga user of a selected mode.
 38. An optical reader according to claim 37,wherein said notifying means is an indicating means, and the indicationform of said indicating means is varied depending on a selected mode.39. An optical reader according to claim 38, wherein said indicatingmeans selects continual indication or intermittent indication accordingto a selected mode.
 40. An optical reader according to claim 37, whereinsaid notifying means is a speaker for generating a notification sound,and the notification sound is varied depending on a selected mode. 41.An optical reader according to claim 37, wherein said notifying means isa means for reporting the result of reading of said mark, and thenotification form for the result of reading to be notified by saidnotifying means is varied depending on a selected mode.
 42. An opticalreader for scanning a mark carried by an article using scanning light,detecting light reflected from said mark, and thus reading informationrepresented by said mark, comprising: a light source; a scanning meansthat is driven by a driving means and scans light emanating from saidlight source; a plurality of reflection mirrors for reflecting scanninglight scanned by said scanning means and creating a scanning patterncomposed of a plurality of scan trajectories; a read window throughwhich scanning light reflected from said reflection mirrors is emitted;a head including a light receiving means for receiving light reflectedfrom said mark; and a grip communicating with said head and enabling auser to grasp said optical reader.
 43. A switch, comprising: a switchbody incorporate din an apparatus; and a switch plate that is attachedto the top of said switch body and that depresses said switch body whenmanipulated; wherein: said switch plate is supported at two or moresupporting points; and when said switch plate is manipulated, saidswitch plate is pivoted in a manipulated direction with said supportingpoints as fulcrums and said switch body is pressed.
 44. A switchaccording to claim 43, wherein said supporting points are threesupporting points arranged in the form of a triangle, and said switchplate is held on said apparatus at said three supporting points.
 45. Astand on which an optical reader, which has a read window through saidscanning light is emitted and a grip enabling a user to grasp saidoptical reader, and which scans a mark borne by an article usingscanning light emitted through said read window, detecting lightreflected from said mark, and thus reads information, is mounted,comprising: a holder section in which said grip is mounted so that saidgrip can be dismounted freely; and a base for supporting said holdersection so that said holder section can pivot; said holder sectionhaving a slit, through which a cable coupled with said optical readercan pass, on the same side thereof as the side of said optical readerhaving said read window.
 46. A stand according to claim 45, wherein aconcave dent is formed from a position on said base coincident with alower end of said grip of said optical reader mounted toward the forwardside of said stand.
 47. A stand according to claim 45, wherein saidholder section has a member to be actuated with an instruction sent fromsaid optical reader so that a state in which said optical reader ismounted on said stand can be reported to said optical reader.
 48. Astand according to claim 47, wherein said member is shaped like a jut,and when said optical reader is mounted on said stand, said memberpushes said instructing means.
 49. A stand according to claim 47,wherein said member is a mark readable by said optical reader, and saidmark is located at a position enabling scanning light emanating fromsaid optical reader mounted on said stand to scan said mark.
 50. A standon which an optical reader, which includes a read window through saidscanning light is emitted and a grip enabling a user to grasp saidoptical reader, and which scans a mark borne by an article usingscanning light emitted through said read window, detects light reflectedfrom said mark, and thus reads information, is mounted, comprising: astand member on which said optical reader is mounted in such a mannerthat said grip of said optical reader will face laterally.
 51. A standaccording to claim 50, further comprising: a holder section in whichsaid grip is mounted so that said grip can be dismounted freely; and abase for supporting said holder section so that said holder section canpivot; said stand member having a tongue, which is inserted into saidholder section so that said tongue can be removed freely, on a bottomthereof.
 52. A stand according to claim 50, wherein when said opticalreader is mounted in said stand member, said optical reader is held atan angle at which at least one scanning pattern, which is composed of agroup of scanning rays, of scanning patterns created by scanning raysemitted through said read window of said optical reader, becomeshorizontal.
 53. An optical unit for an optical reader, comprising: aplurality of reflection mirrors; a laser light source; a light receptionsensor; a condenser mirror that has a plane mirror, which reflects laserlight emanating from said laser light source, around the center thereofand that gathers incident light to said light reception sensor; a rotaryscanning means that has a plurality of reflection surfaces forreflecting laser light reflected from said plane mirror, that is drivento rotate by means of a driving means, and that thus scans said laserlight; and a frame which is molded as a united body and in which saidreflection mirrors, said laser light source, said light receptionsensor, said condenser mirror, and said rotary scanning means arelocked.
 54. An optical unit according to claim 53, wherein said rotaryscanning means is mounted on said frame via a cushioning member.
 55. Anoptical unit according to claim 53, wherein: said condenser mirror hasboth edges thereof supported by said frame; one edge of said condensermirror is supported so that it can move back and forth; the other edgeof said condenser mirror is supported so that it can pivot with an axisof pivoting extending in a longitudinal direction of said condensermirror as a center.
 56. An optical unit, comprising: an optical parthaving a first and second stems formed coaxially on both edges thereofand a third stem formed vertically to said second stem on one of theedges thereof; and a frame on which said optical part is mounted, andwhich includes a first slit-like bearing into which said first stem isfitted, a second bearing into which said second stem is fitted, and athird elongated bearing into which said third stem is fitted and whichforms an arc with said second bearing as a center.